Case Studies

A Collection of the Odd, Unusual and Interesting Found While Servicing Our Client Vehicles.

Originally intended as a showcase for customers of our workshop and staff’s abilities, this page has evolved in an interesting and informative teaching tool, and one of the most popular pages on our site!

By nature, these are rather extreme examples of failures, and not what we typically find during service. Our goal at Atlantic Motorcar is to prevent these from happening to you and your car. But rest assured, if we can fix these challenges, regular maintenance is breeze!

We like to call this our “YES WE CAN!” page. You can also view many of these concerns on our Facebook page. Each photo can be enlarged by clicking on it.

Keeping Your Cool – Air Conditioning (A/C) Recharge System Service Process and Costs

July 6, 2023

Case Studies

Atlantic Motorcar Center

Anticipated Service Cost
If your car’s AC system efficiently drops and is no longer cooling or cooling effectively or has a flashing warning light, it may be running low on refrigerant. Pending finding no gross leaks, it may be as simple as a recharge. This isn’t a costly repair and likely won’t need to be done before you hit the 60,000 to 100,000-mile mark, so any car for five years or older will likely need this done at least once.

For most cars, an AC recharge will cost between $200 to $300, depending on the amount of refrigerant needed (larger vehicles use more refrigerant), including the addition of UV leak detection dye. It’s a straightforward procedure, but it can take a while to check everything out and ensure no further damage.

When to Get an AC Recharge Done?
It’s important to have your AC system recharged, don’t neglect an inoperative system. You can run it for a very short while before there is any serious damage, but you should take care of this problem sooner rather than later. Over time, the lack of refrigerant will put extra pressure on the compressor and other parts of the AC system, making them work harder; plus, any moisture which has entered the system can cause them to break down and require extensive repairs and replacement.

The best way to know if your system needs a recharge is to pay attention to its operation. You may notice that your system isn’t working as well as it should. It may have trouble producing cold air or make weird noises or overheat. These are signs that you need to have some inspection or service needs to be done.

What Is A Recharge System Service
Your AC system runs on a refrigerant. The refrigerant removes moisture from the inside of the car and deposits it to the outside. So you feel comfortable. But over time, the refrigerant will run out. It can escape through normal seepage. Also, major leaks or component failures can deprive the refrigerant. Once the refrigerant is low, the AC will no longer function properly.

Without the right refrigerant levels, your system can overheat and experience pressure that can damage the other components of the AC system. An AC recharge means checking the current pressure levels in the system and recharging it to get it to where it needs to be. This allows everything to operate smoothly, last longer, and produce cooler air.

What Is Done During AC Recharge Service
The technician will want to check for the source of the problem first. If you have a concern about some issue with your AC, we will perform a thorough check of the system to ensure that by recharging your unit, we are taking care of all the problems. You don’t want to pay for a recharge and then find out later that you have a refrigerant leak!

Once the technician sees that the system needs a recharge, he will evacuate all the refrigerant from the system using a coolant recovery machine. Once the parts have been evacuated, he will replace them and remove all the air from the system. The new refrigerant will be installed, and any damaged or worn seals must be replaced. If the unit leaks, one or more seals or hoses are usually at fault. We use a UV Dye test to check for current and future leaks.

UV Leak Detection
As many refrigerant leaks are often not detected until the vehicle has been in service for some time, we have chosen the UV Dye method as the most accurate and cost-effective available.

There are three common ways of finding leaks in the system:
1. Visual. If the leak is very obvious, we will see it with no help.
2. Use of a special UV flashlight and goggles
3. Gas/Refrigerant Leak detector.

This can only be done if the system has enough refrigerant & oil/dye in it to detect a leak, which is why this service must be performed first to determine the source of failure. This test will help us find the largest leak, it is possible that other (smaller) leaks will show up after a larger leak is repaired.

The customer must return at the first sign of loss of cold air; if the system runs out again and rain washes the dye away, this process must be re-done at the customer’s expense. Refrigerant is a greenhouse gas, and it is illegal to vent it out into the atmosphere. Therefore, we are not allowed to knowingly recharge a leaking A/C system.

Benefits of AC Repair
By recharging your AC unit, you will enjoy a system that works more efficiently and lasts longer. The air it produces will be colder, and you will protect the rest of your AC system and the surrounding car parts from overheating and other types of damage. You also enjoy the benefits of an AC system that works like it should every time, providing cold air when needed and keeping your car comfortable.

How We Can Help You
The Service Team here at Atlantic Motorcar is well experienced in this issue and others; with over 35 years of European auto specialization, serving clients from the areas of New England, we are familiar with the needs of the special service of your auto.

As Maine’s leading European auto specialists, we provide expert-quality services at a fair rate than nearby dealerships and specialty shops. If you’re experiencing any of the above-mentioned symptoms in your auto, please call us immediately; we can usually see your car the same day! At Atlantic Motorcar, we’ve developed some very specific procedures and tooling, combined with our expert technicians, to make this otherwise onerous repair a snap.

Finally
Questions or if we can help with service on your Audi, BMW, Mercedes, Sprinter, Honda, Infiniti, Lexus, Mini Cooper, Porsche, Volvo, and VW, don’t hesitate to get in touch with us. Our team of Service Specialists is here to help, for even the newest autos! (207) 882-9969.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Audi, Porsche and VW 2.0 TSI Engines – Rear Main Seal Oil Leaks And Proper Correction

June 30, 2023

Case Studies

Atlantic Motorcar Center

Vehicles Affected
The Audi and VW 2.0L TFSI, TSI, and FSI engines have been around for almost 15 years. During that time, Audi/VW made endless revisions and updates to the hardware and software.

You may have read of the problems with the leaking rear main crankshaft seal on the Audi and VW 2.0 TSI engines. This is a common pattern failure with 2009-2012 Volkswagen Tiguans. We say 2009-2012 VW Tiguans, but the issue can occur on any 2.0TSI Volkswagen, Audi or Porsche (2014+ Macan) using this seal design.

As with all cars, the Rear Main Seal is located between the engine’s crankshaft and the flywheel, which means the transmission must be removed to replace this part. This is a considerable labor operation, so it’s critical to use only the highest quality parts, and fully service the system to prevent repeat failures.

This often first evidenced by a leak of oil under the car, which may be found during a service visit, and later will show up on the ground. The leak can range from a couple drops on the driveway to a pool. In extreme cases, the MIL (Check Engine Light) will illuminate due to a vacuum leak out the seal, as the engine will be running lean, more about that below.

Symptoms and Diagnostics
When the rear main engine seal fails, you will find an oil leak coming from the bottom of the vehicle where the engine and transmission meet. Ensure the leak is not coming from higher up on the engine before deciding the main seal is bad, cam cover gaskets and front timing covers leaks must be handled first. Cleaning the oil from the engine, and the use of an oil based UV Dye Leak Tracer is a good method for confirm the diagnosis.

As the engine uses a sealed crankcase system, you also may experience fault codes like P0171 – System too lean, or misfire fault codes P0300, P0301, P0302, P0303, and/or P0304. It is essential to note that these fault codes should only be considered as potentially related to a bad rear main seal if you are experiencing an oil leak from the area between the engine and transmission where the rear main seal is located and absent an oil leak are NOT a diagnostic indicator for rear main seal replacement.

Causes
Rear engine main seal failures will often be caused by two things, the first, a failed Crankcase Vent Valve and PCV system which causes excessive crankcase pressure (PCV) issues, and the second, the seal design itself.

Crankcase Vent Valve
VW Technical Service Bulletin 2015505/1 discusses increased oil consumption and blue smoke. Upon inspection, oil can be found in the air intake hoses after the turbocharger, and the oil can be seen leaking from the oil filler cap.

The cause of the problem is that the guide pin (see yellow arrow) that is part of the check valve in the intake manifold side of the valve may break, preventing the check valve from correctly sealing when boost pressure is present in the intake manifold. Intake boost pressure will be applied to the engine crankcase, resulting in oil leaks and the prevention of engine oil from properly draining from the turbocharger through the oil return line.

In addition, infrequent oil changes, extended service intervals, or oil changes with the incorrect oil and filter can lead to a build-up of sludge in the engine, and clog or damage the Crankcase Vent Valve and PCV system. Once clogged, the effect of this is too much pressure building up in the crankcase, and the PCV isn’t venting it out correctly. When this occurs, over time, it causes the rear main seal to blow out and begin leaking.

We have also heard possibilities of this issue becoming prevalent due to using incorrect spec oil, but a failed Crankcase Vent Valve and PCV system in fact causes most failures. The part has been redesigned, and there is a superseded part number; always double-check with Audi/VW/Porsche electronic service information to ensure the latest and greatest part is installed.

The Seal Design
The other cause we mentioned is the main seal design itself. The OEM rear main seal utilizes a poorly designed PTFE “sealing lip” in an inexpensive stamp steel housing, which over time and with overpressure, can separate and lead to an oil leak between your engine and transmission.

In the past, the seal was almost always housed in a rigid aluminum rather than stamped steel housing. There is an upgrade for some cars, using a conventional old-school, durable rubber seal, which we highly recommend.

Correction
Because of this issue with the PCV becoming so prevalent, VW has issued redesigned seals that resolve the issue at hand, but do not automatically fix or prevent a pre-existing failed or failing rear main seal.

It is important to note that if you have an issue with your rear main seal leaking on your VW or Audi 2.0T TSI engine, you should definitely replace your Crankcase Vent Valve and PCV system at the same time. Failing to do so may result in premature replacement rear main seal failure. Whenever we replace a rear main seal, we always quote replacing the PCV with the updated version (if it hasn’t been already), the rear main seal, and normally a full synthetic oil change with VW spec oil.

Upgrade
For some cars, a billet aluminum rear main seal kit is designed to replace the failure-prone stamped steel factory part. This billet aluminum rear main seal kit is CNC machined from 6061-T6 Aluminum and features an OEM Viton Elring seal with an integral tension spring to ensure a tight seal to the crankshaft. The OEM rear main seal utilizes a poorly designed PTFE “sealing lip” which, over time, leads to an oil leak between your engine and transmission.

This kit has been tested and proven to last under high heat and is an excellent upgrade for replacing your leaking rear main seal. It is also an outstanding preventative maintenance modification that can save you from future headaches of oil leaks, stained driveways, and reduced performance that a leaky OEM rear main seal brings with it.

VW and Audi 2.0 TSI Engine

VW and Audi 2.0 TSI Engine

Failed Factory Seal

Install of Upgrade Seal Kit

Crankcase Ventilation Valve

Failed Crankcase Vent Valve

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Porsche 911, 912 and 914 – Steering Tie Rod Upgrade Kit – Conversion To Turbo Tie Rods

May 19, 2023

Case Studies

Atlantic Motorcar Center

Background
First off, if you don’t know much about steering tie rods, the basic definition is that it connects the steering rack (in this case, a gear-driven box that translates turning the steering wheel into side-to-side motion to turn the front wheels known as a “rack and pinion”) to the wheel hub assembly (brakes, rotors, wheel, tire, etc.). It “ties” the track to the wheels.

The steering rack is up in the car’s underside, and the wheel hubs both turn and go up and down. So you need something that “ties” it together but can also handle all this movement. So it becomes a very fancy thing that needs two joints to be able to handle the movement. It could be a solid, straight bar if it didn’t have to move up and down and change the angle of motion. But it does. So we have two joints on it to do its job and manage the angles.

Original Porsche Design
On basically all Porsche 911, 912, and 914 models from 1969 through 1989, the tie rods look like the one shown below in the “Old vs New” photo. The exceptions may be cars already serviced and updated. The old tie rod has a normal ball joint at the wheel side (the “tie rod end”) like the new one. But at the other end, the old tie rod has an angled hinge-type joint with rubber bushings. On the outer end, which attaches to the wheel spindle, is the traditional tie-rod end with a ball and socket-type joint on the suspension upright end.

Why Update Needed
However, on the steering rack end, the inner tie rod is a strange-looking joint that houses a rubber bushing. Porsche designed this to help quell steering wheel vibration on their sports cars and installed this rubber bushing rather than the now traditional ball and socket type joint. Given the design and materials of the late 1960s, this rubber bushing was probably not too bad when it was brand new, but over time it wears down, and you lose a lot of steering feel and directness with this nasty old rubber. Again, every air-cooled Porsche used this tie rod style for two decades. That is, every air-cooled Porsche except one.

Then The Porche 930 Happened
It was in 1976, Porsche introduced the 911 Carrera Turbo (type 930) with a 3-liter engine and a turbocharger providing additional shove. It was a phenomenal car, a world-beating car even, an insanely fast car in its day. Because the Turbo was a bit of a handful to drive, Porsche wanted to make sure there was not any steering bind or even momentary delay in the response of the front wheels to the driver’s steering inputs. As a result, they removed the standard tie rod and replaced it with a metal-on-metal ball and socket-type joint at the steering rack.

Recommendation
Since then, Porsche enthusiasts have figured out that the two styles of tie rods are interchangeable and have installed several thousand sets of Turbo Tie Rods on non-turbo Porsches. Which is exactly what we do here. The kit shown below is the Porsche 930 kit, which we retrofit to the early 911s, 912, and 914 we care for.

Porsche 914 Service

Old vs New Tie Rod

Porsche 911 Turbo Tie Rod Kit

Installed

Gator Spring

Turbo Tie Rod Update Kit

Next Steps – Proper Alignment
After the tie rod update, a proper four-wheel tracking alignment must be carried out.
Our workshop uses the Mercedes Benz of alignment machines, the Hunter Hawkeye Elite, recommended by most of the major European auto manufacturers.
There are four key measures to each alignment: caster, camber, toe, and thrust angle, and we’ll explain those below.

Camber
This suspension angle shows how the tire angles away from 0 degrees vertical when viewed from either the front or rear of the vehicle. Expressed in degrees, negative camber means the top of the tire tilts toward the vehicle’s center, while positive camber means the top tilts away from the center. A visual cue for a camber problem is excessive tire wear on the inner or outermost ribs.

Caster
This angle shows the forward or backward slope of a line drawn through the upper and lower steering pivot points when viewed directly from the side of the vehicle. Also expressed in degrees, caster is measured by comparing a line running through the steering system’s upper and lower pivot points (usually the upper and lower ball joints of an A-arm or wishbone suspension design or the lower ball joint and the strut tower mount of a McPherson strut design) to a line drawn perpendicular to the ground. Caster is said to be positive if the line slopes toward the vehicle’s rear at the top, and negative if the line slopes toward the front. A visual cue for a caster problem is serious tire scrub laterally across the tread face.

Toe
Identifies the direction in which tires are pointed relative to the vehicle’s centerline when viewed from above. Toe can be expressed in either degrees or fractions of an inch. When looking down upon a vehicle, “toe-in” is when the leading edge of the tire is pointed toward the vehicle’s centerline. Conversely, “toe-out” refers to a tire face that points away from the vehicle centerline. The toe setting is typically used to help compensate for the suspension bushings’ compliance to enhance tire wear. Service Tip – The toe alignment also can be used to adjust vehicle handling; for vehicles that “wander,” the toe can be set slightly more toed in for directional stability.

Thrust Angle
Consider an imaginary line drawn perpendicular to the rear axle’s centerline. This measure, expressed in degrees, compares the direction in which the rear axle is aimed at the vehicle’s centerline. The thrust angle also confirms if the rear axle is parallel to its front axle and that the wheelbase on both sides of the vehicle is the same. If the thrust angle is incorrect on a vehicle with a solid rear axle, it often requires a trip to the frame straightening shop to correctly reposition the rear axle.

Tech Note
There are various reasons for any of these alignment measures to be incorrect. At the same time, adjustment angles can be adjusted by a skilled technician to correct for inherent vehicle problems, correct for unusual tire wear, or to improve the performance and feel of a vehicle.

Alignment Specifications
All vehicle manufacturers have set specific alignment specifications for each vehicle. These are the “preferred” angles for camber, caster, and toe (with the preferred thrust angle always being 0 degrees). OEMs also provide the acceptable “minimum” and “maximum” angles for each specification and are usually within plus or minus one degree of the preferred angle.

Vehicles With Steering Angle Sensor
Sometimes, an additional labor operation must be performed to calibrate the steering angle sensor. The Steering Angle Sensor is what tells the onboard system if the steering wheel is pointing straight, left, or right and by how many degrees. Suppose the steering angle sensor data does not match with the rest of the vehicle data. In that case, the traction control system will likely trigger a plausibility error because the car doesn’t match what the steering angle sensor tells it. As mentioned, this is a separate labor operation from a standard four-wheel alignment and will be billed separately.

Finally
Questions or if we can help with service on your Audi, BMW, Mercedes, Sprinter, Honda, Infiniti, Lexus, Mini Cooper, Porsche, Volvo, and VW, please contact us. Our team of Service Specialists is here to help, for even the newest autos! (207) 882-9969.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Bosch CIS (Continuous Injection System) or K-Jetronic Demystified

May 18, 2023

Case Studies

Atlantic Motorcar Center

Background
So you bought a vintage Audi, BMW, Mercedes, Saab, Volvo or VW with the Bosch CIS fuel injection system. To which I say, “Cool” I cut my teeth on CIS as a young tech back in the 80s and 90s, and have a strong fondness for the system. The design is typically German, simple, reliable, and very ingenious.

Bosch CIS Is K-Jetronic
Bosch CIS (Continuous Injection System) or K-Jetronic, has earned an unfair reputation as being difficult to service as it is largely a hydraulic system relying on pressures and pressure differentials to function.

No Scan Tools
One can’t just plug into it with a scan tool and find answers; it requires understanding how the system operates to know normal and abnormal parameters. On the other hand, since it is largely a mechanical system, there are far fewer things to go wrong with it, and it is nearly bulletproof.

Theory Of Operation
The Bosch K-Jetronic (K-Jet) system comprises different components, which are discussed below, and their functions. Only the components related to the system are shown below. The K-Jet system belongs to the group of CIS injection systems, which stands for “Continuous Injection System.” This means that the fuel is continuously injected into the inlet manifold. The system is completely mechanical, relying on pressures and pressure differentials to function.

From the end of 1979, this system was modified by adding a lambda control system (oxygen sensor to create a closed-loop mixture control system. This new system was known KA-Jetronic, or K-Jet with Lambda. This system is shown in the figure below; the components 11, 12, 16, and 18 are specific to this lambda control system and are, therefore, not present in a mechanical K-Jet system.

From Cold Start
Let’s take it from a cold start. Cranking the starter triggers the cold start valve to spray into the intake plenum on early models. Due to flooding problems, a thermo-time sensor was added to prevent the cold start valve from spraying fuel for more than 8 seconds and when the engine temp is warm.

The control plunger inside the fuel distributor moves according to how much air deflects the air sensor plate and is also affected by control pressure. Control pressure acts on the top of the control pin; cold control pressure is low, about 1 bar (15 psi), depending on the model, which lessens the resistance of the air sensor plate to rise. As the engine temp comes up, the control pressure rises, and the resistance increases leaning out the mixture (hot control pressure is about 3 to 3.5 bar (50 psi).

The internals of the fuel distributor determines how much fuel is output to the injectors. There are two chambers separated by a stainless steel diaphragm; the lower chamber is system pressure set by a small spring and is adjustable but almost never necessary. When the control plunger rises, this allows system pressure into the upper chamber; once the pressures in both chambers are equal, the spring pressure deflects the diaphragm and let’s fuel out to the injectors. Note the diagram below.

So let’s look at each component of a typically K-Jet system.

1 – Fuel Tank
Unfourtantly its greatest enemy is water, which wreaks havoc on the small metering passages in the fuel distributors and filter screens in injectors and ports.

2 – Fuel Pump
The fuel pump is used to supply the system with the necessary fuel pressure. A non-return valve is installed just after the fuel pump, which is needed to keep the system pressurized after the engine has been switched off; this allows for easy warm starts. The design is an electrical roller type with a check valve to prevent backflow and a relief valve in case of restriction.
system pressure = 80 psi or 5.5 bar (14.7 psi = 1 bar)

3 – Fuel Acculator
The fuel accumulator has two functions:
– After the engine is switched off, this accumulator keeps the fuel system under pressure to promote a warm start.
– The accumulator dampens out the fuel pulses generated by the fuel pump. A large spring-loaded diaphragm to keep fuel pressure up with the engine off also dampens pulses from the pump.

4 – Fuel Filter
The purpose of the fuel filter is to filter the fuel so that it does not pollute the system. Keep the filters clean; we now recommend replacement yearly and water out of the tank (which goes for extended sitting with alcohol fuel), and the system lasts nearly forever.

5 – Warm Up Regulator / Control Pressure Regulator
The purpose of the warm-up regulator is to help enrich the fuel mixture during a cold start. The mixture is adjusted to the correct ratio when the engine warms up. This component can be overhauled, and we have had great success in cleaning and servicing these units, many of which are no longer available. An electrically heated bi-metallic strip operates a valve controlling fuel pressure to the distributor. Some units have a vacuum diaphragm that provides enrichment during acceleration.

6 – Fuel Injector
The injector provides a nicely atomized fuel to make the fuel-air mixture as homogeneous as possible. Not an electrical design; think of it as a mechanical valve that “pops” when the fuel pressure reaches approximately 45 psi (3 bar). All injectors in A K-Jet system spray at the same time the same amount; there is no timing as with a mechanical injection system. These are usually quite reliable, as long as water or debris doesn’t enter the fuel system. They do have rubber o-ring seals that need replacement from time to time.

7 – Cold Start Fuel
Discharged from the Cold Start Injector is present only when the engine is cranking over, as the operating voltage is derived from the starter solenoid.

8 – Cold Start Injector
Working in connection with the Thermo-time switch, the cold start injector adds extra fuel at very low ambient temperatures to assist when starting the engine. These only operate when the engine is cranking over, as the operating voltage is derived from the starter solenoid.

9- Fuel Distributor
The fuel distributor is the mechanical heart of the system, supplying the different cylinders with exactly the same amount of fuel. Some versions have an internal fuel pressure regulator to keep the system pressure constant. The main moving part is a central plunger which is controlled by the air sensor plate. When the throttle is opened, the increase of air into the manifold causes the air sensor plate rises and pushes the control plunger which allows fuel out to the injectors. Mixture adjustment is via the 3 mm Allen screw. This part can be serviced or rebuilt only with great care and proper tools. This is very easily damaged by debris or water in the fuel.

10 – (Mechanical) Air Flow Meter
The mechanical air flow meter measures the amount of air drawn in by the engine by employing a “teeter-toter” pivoting lever to access the metering plunger in the fuel distributor. Based on this measurement, the fuel mixture is mechanically adjusted. These are quite robust and rarely require service or adjustment.

11 – Frequency Valve / Timing Valve
This control valve is used with KA-Jetronic systems. Here the fuel mixture is regulated by means of a lambda-probe control system. The control valve changes the pressure between the upper and lower chamber of the fuel distributor, thus changing the fuel mixture.

12 – Lambda (Oxygen) Sensor
The lambda-sensor (only on KA-Jetronic) generates a signal that the control unit uses to adjust the fuel mixture. A special ceramic material that senses the difference between the O2 in the exhaust (or lack thereof) and the ambient O2 and produces a voltage that is sent to the Lambda Control Unit to adjust the CO in a closed loop system. The voltage fluctuates between a few millivolts and just less than 1 volt. The early single-wire (unheated) lambda sensor only generates a signal if the component has a sufficiently high temperature.

13 – Thermo-Time Switch
The thermo time switch controls the injection time of the cold start injector (8). If a lambda control system is fitted, this sensor is also used as an input for the control device (computer) (18).

14 – Igntion Distribotor
It is not directly connected to the CIS system, noted only for diagram continuity.

15 – Auxiliary Air Valve
The purpose of the auxiliary air valve is to supply more air when the engine is cold. This air slide can be operated electrically or can be directly connected to the coolant system to change the system state.

16 – Throttle Position Switch / Position Sensor
The throttle switch is only used in systems with a lambda control system. This switch is present so that the control unit knows the throttle position for idle speed control.

17 – Engine Control Unit / Computer
The control unit (ECU) processes the various inputs to provide the desired signal to the control valve (11), thus optimizing the fuel mixture. This unit is only present with KA-Jetronic systems or K-Jet with Lambda.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Porsche 911 – Smoking On Start Up – Q & A And The Why

May 16, 2023

Case Studies

Atlantic Motorcar Center

Background – Recently, we had a client ask us about slight oil smoke at the start up of his Porsche 911. If one person asks, it usually means that at least ten other folks have the same question. So, we thought sharing this here might be a solid idea.

Question – “Hi Bruce. Thank you for the follow-up note. Much appreciate your work on my Porsche 911. Question – when I start it up cold, It does blow some smoke. How concerned should I be? Or not. It’s got 45k mileage and is now ten years old.

Answer – Very common with 911 to have some slight smoke on start up. It’s the nature of the Porsche flat 6 engine that oil can seep into or past the rings when the engine has been sitting some time. It should clear up in a few minutes of running.

Technical Reason
The technical answer is that the smoke on start-up is caused by the engine “wet sumping”. That is, some the oil in the oil tank drains down into the crankcase overnight. The 911 engines are a dry sump oiling system. This means, that the crankcase is purged of oil when the engine is running.

Also if your oil tank level is slightly too high the sump can fill and oil can enter the cylinder, via the rings and cause the smoking at startup. Even a different parking angle can cause this condition. Once the engine is stopped and over time, the oil works down into the crankcase and floods the bottom end. That oil level is now backed up against the pistons and crankshaft.

Once re-started some oil has saturated the piston ring packs and the crank webs, and you get smoke till it burns off. It is not a problem once running as the oil pump has a pressure side and a scavenge side. The scavenge side has much more pumping capacity than the pressure side and quickly empties the crankcase of oil. The trick to keeping a 911 from smoking at start-up is to drive the car every day and be sure there are no air leaks in the breather (that long hose from the back of the engine to the top of the oil tank).

Link
A link to an excellent article with more detail can be found at – https://tinyurl.com/911engineoildesign.

Avoiding This
Factors that make it less likely include a good service history and a usage that isn’t inner city or predominantly short journeys (where the engine is always running with a rich mixture and excess fuel can dilute the oil). The 20K/2yr service intervals also haven’t helped with engine life when diluted oil isn’t often changed in such an urban environment.

Preventative Maintenance
We would strongly advise changing your car’s engine oil every six months or 5,000 miles, preferably with oils formulated with increased levels of Moly additives that most oils do not have, which in turn helps to protect the cylinder walls. Doing so will help the oil remain free of contaminants that could lead to Porsche cylinder bore scoring. Models that have been well maintained with good service history and a healthy cooling system will reduce the chance of localized overheating. More frequent oil changes may be necessary if you track your car, drive short distances, or operate the engine in cold climates.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Porsche Cylinder Bore Scoring – Our Thoughts On This – The Simple Truth

May 4, 2023

Case Studies

Atlantic Motorcar Center

True Bore Scoring – Photo LN Engineering

Porsche M96/M97 Bore Scoring
There are many articles online and various posts in Porsche forums about bore scoring issues and engine failure; if one were to believe what they see online, they’d think it was an endemic problem. The simple truth is that while cylinder bore scoring has been an issue on a relatively small percentage of 996 and 997 models, it isn’t a universal problem.

If you look at the photo gallery below, you will see typical wear and light scoring found in almost every car on the road. This is not a reason to panic, but rather a reminder to take extra care and precautions with your Porsche. Below we’ll share our feelings on this issue and what you can do to mitigate it, or ideally prevent it from occurring in the first place.

How Does It Happen?
The M96/97 Crankcases use ‘Lokasil’ Cylinder liners (a flexible but hard-surface metal matrix composite), and due to the layout of the open deck crankcase on 996/997 models, the cylinder banks are not rigidly supported like the first generation 928, 944 & 968 water-cooled engines. Another factor in the M96/97’s engine design is the difference in lubrication and cooling.

The oil spray and coolant face the lower side of the cylinders, which means the piston thrust on the right side cylinder runs slightly hotter than the left side. This results in the sixth cylinder becoming hotter when thermal and mechanical stresses are applied across the two banks of cylinders. This, in turn, causes the sixth cylinder to become slightly oval in shape, causing more friction between the cylinder and the wall, which results in the cylinder lining being rubbed away.

Once the protective cylinder lining is damaged, the cylinder is in direct contact will the wall, which causes scarring. In addition, lubrication of the cylinders is also compromised by a two-year oil change interval (DON’T DO THAT!). When fuel and moisture contaminate the oil (due to low mileage short journeys), the oil becomes diluted, which results in friction between the piston and the cylinder bore wall and localized overheating.

Borescope Results For Porsche 911 (Click to enlarge)
Other than cylinders 5 and 6, we’d consider this normal wear on this engine. Cylinders 5 and 6 show some marking, but nothing compared to what would think of as severe bore scoring, as noted in the LN Engineering image above. A stuck piece of carbon, other impurities, or a high engine rev on a cold engine might have caused the slight galling present on cylinder 5, whereas cylinder 6 looks like some debris was caught in a piston ring. Dirty engine oil, extended change intervals, or low-quality oil may have also contributed to it.

Porsche 911 - Cylinder 1

Porsche 911 - Cylinder 2

Porsche 911 - Cylinder 3

Porsche 911 - Cylinder 4

Porsche 911 - Cylinder 5

Porsche 911 - Cylinder 6

Addtional Reading
A full in-depth article on this issue and other export opinions can be found here by our friends at LN Engineering –
https://lnengineering.com/products/watercooled-porsche-cylinders-sleeves-and-pistons/bore-scoring/tips-on-how-to-prevent-porsche-bore-scoring.html

Porsche Models Prone To Bore Scoring
All water-cooled 911’s Boxsters and Caymans from 2004 through to 2009 are at risk of suffering from bore score; however, it would appear the percentage of engines actually affected is actually quite low.

“Porsche GB advised that it sold 9710 E 996s and 997s in the model years 2004-2006. Some very wet-finger-inthe-air guesswork suggests independent specialist rebuilds and OPC warranty replacements combined may have reached 500 engines from that period, which indicates an overall percentage of around five percent.” (Source: GT Porsche Magazine)

Symptoms of Bore Scoring
• A rhythmic ticking noise that sounds similar to that of a hydraulic lifter
• One exhaust pipe has more soot than the other
• Increased oil consumption
• Extremely black engine oil
• Pooling of oil within the cylinders
• Aluminum debris was found in the oil filter and engine oil sump.

Realize It’s Not The End Of The World
Consider that for an engine that has traveled 60,000 miles; each piston has gone up and down over 300 million times on average, leading to serious damage and, potentially, eventual engine failure if the required preventative maintenance has not been carried out. Slight to moderate bore scoring is not the end of the world or the end of your engine. It may increase oil consumption or provide an occasional puff of smoke at start-up, but in no way does slight to moderate scoring indicate the need for engine teardown. Engines like this might last 30K, 40K, 50K, or even 100K miles before the effects are severe enough to warrant attention. It is something to be aware of, to try and mitigate, but we don’t believe that it deserves the amount of attention that is often focused on it on the internet. Run your car, enjoy it, and don’t worry.

Avoiding This
Factors that make it less likely include a good service history, a healthy cooling system (to reduce the chance of localized cylinder overheating during the warm-up or over-run), and a usage that isn’t inner city or predominantly short journeys (where the engine is always running with a rich mixture and excess fuel can dilute the oil). The 20K/2yr service intervals also haven’t helped with engine life when diluted oil isn’t often changed in such an urban environment.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Porsche 911 (Type 991) – Engine Cover Latch Release Problem, and Correction

April 30, 2023

Case Studies

Atlantic Motorcar Center

The Vehicle
The Porsche 911, type 991, is prone to a common problem relating to the remote release of the engine deck lid from the passenger compartment. We recently saw this at Atlantic Motorcar Center with a new client car and thought it would make an excellent case study.

How This Happens
It is not uncommon when service is being carried out on the car for the actuator, the electromechanical device that pulls on the cable, to become disconnected from the rear deck lid latch or to be moved out of the bracket on the actuator itself. This prevents the rear engine deck lid from opening. The actuator and cable are located on the passenger side of the engine bay, very close to the engine oil filter, and with the tight space, it is easy to knock the cable loose. This might not even be discovered until the next time service is done and the rear engine compartment can not be opened. Porsche has an emergency release cable in place in the event of an actuator failure, but this is only useful in the event that that cable is still attached to the latch.

Generally, there are three failures if you have a problem with the rear engine lid not opening. This tech tip will give you information on how to diagnose the nature of each failure and then how to gain access and correct it without damaging the car.

Problem
The first failure would be a failure of the latch actuator itself. The lock actuator is like an electric motor that pulls on the cable attached to the latch. Should the lock actuator fail, this is easily overcome by the emergency release located under the rear spoiler. That releases a cable that is attached to the end of the lock, actuator latch, and actuator, which allows you to remotely unlock the rear engine cover in the event of an actuator failure.

Trust But Verify
If you have access to an engine borescope, you can likely sneak that under the rear spoiler when it’s raised and over or under the plastic engine fan housing to get a view of the latch. You’ll note on the picture here that we could verify that the latch cable had popped out before disassembly. This can save considerable time and effort to understand if it is simply an electrical fault that can be reversed easily or a cable or latch issue, necessitating a more complex solution.

Failure Mode One – Actuator Or Controls
It’s easy to diagnose a failure of the actuator if, when operating the rear deck lid switch in the passenger compartment, you don’t hear the actuator motor run, which sounds like a whirling noise that lasts for about 2-3 seconds, then chances, are you have a failure of the actuator, the switch or the wiring and voltage supply. You still should be able to access the emergency cable and open the deck lid so you can diagnose and correct the problem.

Failure Mode Two – Cable To Bracket
The next cause is a failure of the cable which retains which connects the actuator to the latch itself. The cable itself is quite robust and unlikely to break on its own accord. However, because of its proximity to the engine oil filter, which is commonly accessed during service, it’s easy to knock the latch actuator cable out of the metal bracket on the actuator side. If this occurs, even the emergency cable will not allow access to the engine compartment, as the latch actuator cable is no longer properly connected, and the sheath will move back and forth. We’ll talk about how to overcome this failure mode shortly.

Failure Mode Three – Cable To Latch
The final cause of failure, and perhaps the most common, is when the latch actuator cable becomes disconnected from the latch itself. In this case, the plastic retaining clip that holds the cable onto the latch becomes displaced, which often occurs during service or changing the engine oil filter due to its proximity. If this occurs, even the emergency cable will not allow access to the engine compartment, as the latch actuator cable is no longer properly connected.

Why This Happens
Porsche has made no provision for positively anchoring the cable line into the latch; rather, it is not retained by a screw or bracket and only requires a small bump to become disconnected and misplaced from the latch. When this occurs, and it is not noticed before the engine cover is closed. Access to the engine cover is impossible, either through the emergency cable or the latch actuator. The cable will still move, but because it is no longer attached to the latch release arm, it does not operate the latch.

Photo Gallery – Visual Of Our Process

Protect the car

Use borescope

Remove rear bumper and carrier

Carefully remove air inlet and rubber boot

Fabricate metal retainer on latch to hold cable securely

Magic 911 trunk release tool

Correction – First, Do No Harm
The important thing is to protect the car from any damage; the correction, though it takes time, it’s not exceptionally difficult, especially with an automotive lift and the assistance of a teammate. We suggest using blue painter’s tape on any sharp edges, corners, or exposed areas of the paint to protect the finish.

Step One
The next step is to remove the rear, bumper, and carrier from the vehicle; this does take some time and will require the assistance of a teammate to ensure the damage does not occur, either to the car or to the bumper cover. Once the bumper cover is removed, it can be placed on top of large trash, container, or workbench to protect the finish from damage.

Step Two
With a bumper cover removed, you’ll need to remove the air intake boot from the engine and throttle body to access the area directly under the engine cover latch. If you’re very lucky, you may be able to snap the cable back into the latch and then use the remote control inside the car to operate the cover.

Step Three
If you find that difficult, the next best solution is to simply fabricate out of a stiff wire at a 90° angle pic, with a gentle bend to get around the engine. Using a mirror and a flashlight, place the end of that pic inside the area of the rear deck lid latch, where the cable normally goes, and operate the latch to the passenger side of the car until the rear deck lid opens. It will take firm and steady pressure rather than a fast pull.

It may take several tries with this method before you have success. Take your time, and ensure that no damage occurs to you or the car. If the latch still does not release, it is possible that you have a mechanical problem with the latch itself. You can still access the latch retaining bolts, two 10 mm bolts, from underneath, and once unbolted, raise the deckled to remove the failed latch.

Step Four
Once you have the rear engine cover open, you’ll need to remove the plastic cover that retains the two cooling fans on top of the engine. Be careful of the two wires that are used to power the fans; the connectors are small and can be fragile from the heat of the engine bay. Once you have that fan cover removed, you should be able to look in the center back portion of the engine bay and locate the release latch in the center back of the opening.

Step Five
We suggest removing the latch from the body of the vehicle. You’ll find it retained by two 10 mm bolts about an inch or so long. Removing those is easy, and you’ll probably find factory marks already described on the latch to show you its installed location; if not sharpie or grease pencil can be used to create your own witness marks so that the latch may be reinstalled in the correct position.

Step Six
Once you have removed the latch, you can install the cable carefully, snapping the retaining clip on the passenger side of the latch in place. You’ll note that that is not a very secure connection, and although it may work, it would be easy to displace again. May be a good idea to clean and lubricate the latch with some silicone spray.

Before testing the latch in the actuator, make sure the cable end closest to the actuator is actually snapped into the black metal bracket. If this is not snapped into the bracket, the cable will not operate correctly, as the sheath will move back and forth.

Final Step
With a cable verified to be correctly installed on both ends, we suggest operating the actuator a few times to verify the latch is working correctly before remounting it onto the body. Once the latch is installed back onto the car and lined up with your witness marks, close the rear engine lid and verify latch operation and release. Do it several times just to be sure that it is reliable.

The Fix
While the actuator cable is retained with the plastic positive clip, we’re a big fan of the belt and suspenders approach and suggest fabricating a small metal bracket that can be placed under the passenger side latch retaining bolt removed earlier.

If you look at our picture, you can see that the short bracket, less than 2 inches long, covers and positively retains the actuator cable into the latch body. The cable can only be removed in the future by loosening one of the 10 mm bolts and rotating the bracket out of the way.

Check Both Ends
While this is an elegant solution to the problem on the latch end, one must still be cognizant of the potential ease of knocking the actuator and the cable out of the bracket there. Consider a carefully placed back nylon wire tie, or perhaps, just a check process to make certain on service that the lock actuator works before closing the engine cover. And then retest after the service is complete.

Reassemble In Reverse Order
At this point, with the latch reinstalled, the small bracket fabricated, and the operation of the latch thoroughly tested, simply reverse the process, reinstalling the air, boot air boxes, and rear engine cover, carefully lining everything up. Remove the blue painter’s tape placed for protection, and you should be ready.

Watch The Video
You can review a narrated short video of this tech tip on the Atlantic Motorcar YouTube page; see below.

How We Can Help You
The Service Team here at Atlantic Motorcar is well experienced in this issue, and others, with over 35 years of European auto specialization, serving clients from the areas of New England, we are familiar with the needs of the special service of your auto.

Finally
Questions, or if we can help with service on your Audi, BMW, Mercedes, Sprinter, Honda, Infiniti, Lexus, Mini Cooper, Porsche, Volvo, and VW, please contact us. Our team of Service Specialists is here to help, for even the newest autos! (207) 882-9969.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Porsche 944 and 951 – Balance Shaft Alignment During Timing Belt Service

April 12, 2023

Case Studies

Atlantic Motorcar Center

AMC Tech Tip – Porsche 924/944/951 Balance Shaft Alignment
We have a very nice 951 in the workshop today that came in with a very noticeable vibration. Engine mounts had been recently replaced at another shop, apparently in an attempt to correct this.

Tis The Season

Spring is the season for Porsche 924/944 timing belt calls and quotes, and invariably someone always needs one “redone” because all the parts were not replaced or replaced correctly.

Important – No Shortcuts

There is a huge temptation to do the “economy job” on these, but this is a false economy, and over the years, I’ve seen timing belts replaced with the old balance shaft belt and tensioners left. They rarely make it to the next service, which results in significant engine damage when they fail. Do it right the first time, and you won’t have to pay twice.

Easy oversight on this job is to mistime the balance shafts, so the weights on the shafts, which are meant to cancel out the engine vibration, actually ADD to it. Not a good thing.

Service Tips
There is real science and trick to doing this correctly, and over the last 30 years, we’ve corrected many of these that have come out of other service facilities. I’ve even made a mistake a few times but caught it quickly.

The trick in these cars is to be sure that not just the timing belt is replaced; you’ll want to ensure the water pump (driven by the timing belt), rollers, and tensioners get attention. Also, a quick look at the camshaft, crank, and balance shaft seals will save you headaches in the long run.

Questions, we’re here for you and your car!

Your Advocate, On Your Side
At AMC, because we are independent and locally owned, we are YOUR advocate. Knowledge, Integrity, Value.

Questions
If you have any questions, or need a copy of your service history, please do not hesitate to contact us directly. (207) 882-9969.

Thank you,
Bruce and the AMC Team

Porsche 944 and 951 Timing Belt Service – Doing It Right

April 4, 2023

Case Studies

Atlantic Motorcar Center

Porsche 944 and 951 Timing Belt Service – Doing It Right
The recommended timing belt replacement interval for the 944 engine is every 30,000 miles, to which we would also add a time interval of 3-5 years.

As the timing and balance shaft belts being rubber, deteriorate over time, these vehicles are now rarely driven more than 3,000 to 5,000 miles per year.

Timing belts are made of very durable rubber, with layers of cord to prevent stretching. This arrangement provides years of trouble-free service and precise valve timing. Eventually, the rubber and cords begin to deteriorate. Our rule is 3 -5 years at most.

Due to the normal expansion and contraction of the 944 engine, Porsche recommends that the engine is at room temperature (68 degrees) when replacing the timing belts. Installing the belts at a different temperature will cause an incorrect belt tension adjustment because the engine expands and contracts as it heats and cools.

Important Service Note – New belts should be re-tensioned after their first 2000 miles of use and again after another 15,000 miles.

Why – Engine Damage
All 944 engines are interference engines. The valves and pistons have an overlapping space on interference engines, hence the name interference. If the piston is at the very top of its stroke and the valve is fully open, the valve and piston will collide. The timing belt controls the opening and closing of the valves. The Porsche 944 timing belt is made of rubber and therefore is susceptible to normal wear and tear.

Additionally, it can loosen over time or even completely snap if the rubber becomes torn, brittle, or excessively worn down. Because the engine is an interference engine, when the 944 timing belt breaks, it sends the valves and pistons colliding with each other. The end result is bent valves and potentially damaged pistons. Replacing valves and pistons will require the engine to be opened up, which is labor-intensive and expensive.

Service Plan – Design Changes
The 944’s timing belt design has been upgraded several times since the first car rolled off the assembly line.
Some of these changes were field fixes, and others were production updates.

The updates began in Porsche 944’s first model year, with most of the updates occurring between 1984 and 1986. Almost all the cars have now had the updated parts installed, the most common being the use of the 951 water pump, with guide rail and outlet block-off plate. But you might be surprised from time to time by what you find out there. Original cars with super low mileage and only the timing belt changed or aftermarket parts installed, even balance shaft belts installed incorrectly, result in significant engine vibration.

Upgrade/Update
Each of the following parts have been changed as part of the service upgrade process:
• Belt design
• Camshaft belt tensioner
• Balance shaft belt preload tensioner
• One-piece timing belt cover modification
• Two-piece timing belt cover
• Shaft seals
• Water pump

A Word About Water Pumps
We are frequently asked about reusing water pumps on the engine when the timing belt is serviced. And while that might sound like a good idea, remember what the pump is, and what the consequences are of failure. Water pumps circulate coolant through the engine. They are generally a pretty common maintenance item for all cars.

Why do water pumps fail? Water pumps naturally fail over time from wear and tear and old age. The Porsche 944 water pump fails for a few different reasons. First, the internal bearing can go bad, which will cause a “bearing” noise from the water pump. Secondly, the impeller can separate from the shaft, or the shaft seal can go bad, which will cause coolant leakage. Lastly, the pulley connecting the water pump to the timing belt can slip or break and cause engine failure.

However, they are known to fail a bit more frequently on the Porsche 944. The 944’s water pump is driven by the timing belt, which is also why we recommend replacing them at the same time. A water pump issue necessitates the removal of the timing belt and engine covers to replace, so might as well do it correctly the first time. The cost of a pump is far less than the cost of an engine or engine repair.

Quote It Right – Don’t Get “Slapped”
We must know what you are buying when pricing a timing belt replacement. Some companies quote a phone price for replacing the belt alone, in a less than ethical way to get the car there. Quality auto repair shops refer to this as a “belt slap” (you’ll also hear the “slap” term on shops that just “slap on” brake pads without the full service. This may seem like savings until they call back with the real cost.

Perhaps worse is only replacing the belt, only to have another component fail, for instance, if the water pump fails a few thousand miles after the timing belt is replaced. Repair means another full disassembly, and the water pump can actually cause the replaced timing belt to break, causing engine failure.

Another problem is a seal that starts to leak after timing belt replacement. The seal could have been replaced for a minimum cost while the timing belt was off. Now many of the same components must again be removed. Worse, the oil from the leaking seal can ruin a new timing belt. Remember, you never get more than you pay for.

The Only Correction Is Prevention
An once of prevention (as in a replacement of the timing belt, BEFORE failure) is worth a pound of cure.
If your Porsche qualifies, and the timing belt has not been replaced in the last 3-5 years, we strongly advise you do it proactively.
Do not wait, time is engine. Your engine.

Need More Help?
We hope we’ve been able to shine some light and help you better understand what exactly a timing belt is and what can actually go wrong with them. And more importantly, how to prevent that from occurring! To discuss the best approach for your car, give our service team a call us or email service@atlanticmotorcar.com.

Finally
Questions, or if we can be of help in any way with service on your Audi, BMW, Mercedes, Mini Cooper, Porsche or other European import, please contact us.
Our team of Service Specialists is here to help, for even the newest autos! (207) 882-9969.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.
Thanks!

Warmly,
The Atlantic Motorcar Center Service Team

Helping Your Car Live Longer – The Truth About Rustproofing and Corrosion Protection

December 7, 2022

Case Studies

Atlantic Motorcar Center

What We Think At Atlantic Motorcar
Talking about rustproofing is much like arguing over which is better, chocolate or vanilla ice cream.
Everyone has an opinion, and everyone is sure their opinion is right. What we are basing our recommendations on are nearly 40 years of European automotive service experience, as well as practical day-to-day observations.

It’s important to note that what we share here applies to late-model European autos with their excellent and extensive factory rustproofing systems. It’s also important to note that Atlantic Motorcar does not do rust-proofing; we leave that to the professionals who enjoy working with tar and wax. 😉

Our Recommendation For European Autos
We generally don’t recommend aftermarket undercoating on German autos, they are very well undercoated from the factory, and often a second coat of undercoating serves to dirt and moisture, which is not a good thing. Even the oil spray that you’ll often see advertised can do more harm than good. It can damage rubber components if not carefully applied, make a mess in your garage or driveway, and makes it difficult to determine if the vehicle has any fluid leaks when in for service. For Land and Range Rovers, especially vintage models, we do recommend a proper and professional application of the oil-based systems.

Our opinion on rust prevention varies for domestic and Japanese cars and trucks, from washing them often in the winter to keeping them wet with spray oil treatments. See our Prevention section for more details. So for non-European vehicles, read on.

The Exception
The exception to this rule is in case of body damage; in that case, ensure that the body shop caring for your car reapplies a professional rust protection system on the new or damaged sheet metal. When you see a late-model European car with rust, it is almost always a result of accidental damage that was not professionally repaired and protected.

Rust Proofing History
Remember “Rusty Jones,” the iconic character of an automotive rust-proofing chain two or three decades back?
Or the exotic-sounding “Ziebart“? Probably not, as the big chain rust-proofing shops have largely disappeared over the years as manufacturers have stepped up their factory undercoating systems and metal treatments.

Add in better vehicle design, newer metals, and factory corrosion treatments, with body side moldings no longer held in place with metal clips that promote rust but instead now use an adhesive, and many of the former rust hot spots have disappeared. In fact, our friend Rusty Jones Inc. filed for bankruptcy protection in 1988, claiming that automakers’ extension of factory warranties against rust had caused business to deteriorate.

Better Living Through Design
To better understand the present, it often helps to look to the past. In the early days, cars were just built, they were basic conveniences to get down the road and not expected to last a long time, so little thought was put into durability from a body standpoint, and the sheet metal quality varied widely. Early cars were built on a heavy metal backbone, called a “frame,” with large, heavy components, like the engine, transmission, and suspension, attached to the steel frame. The car body, often of thin sheet metal, sometimes built over wood in earlier cars, served to keep the driver dry in the rain and warm in the winter. And perhaps to add a styling element to the vehicle.

Various types of high-strength steel are found in today’s cars. The blue color is the “crumple” zone, designed to absorb impact energy, and the red is the high-strength steel to build the protective passenger cage.

Today’s cars are very different because the frame system has largely disappeared on most passenger cars and SUVs. Engines and transmission bolt directly or indirectly right to the sheet metal. The body of the car is now not just a structural component that needs to support the engine and transmission but is also a carefully engineered safety system, with crumble zones and various high-strength steel and aluminum parts to protect the occupants.

It’s also become common for manufacturers to use galvanized steel in their vehicle frames. With a zinc coating, galvanized steel doesn’t react with oxygen like iron, significantly reducing the risk of rust. Cars built these days aren’t going to rust out as you’d see decades ago completely. Factors like the climate you will be driving in, the terrain you will be driving on, and the amount you will be driving affect the degree of rust. Rust-proofing will make more sense if your vehicle is regularly subjected to the elements, but if you mainly plan to do city driving in a warm climate, chances are it is optional. Plus, many manufacturers now offer a factory warranty to cover rust and sheet metal perforation, as we read above that our friend Rusty Jones sadly found out.

Rust-Proofing Treatments and Types – Tar and Oil
There are two primary forms of aftermarket rust-proofing today: tar-based spray and oil/paraffin mix.
Both have pros and cons, as outlined below, and it’s important to consider which might work better for you.

Tar Based Sprays
Let’s start with the tar-based spray. You’ll often see this type of coating in cans at your local auto parts store. Also known as “undercoating,” tar-based sprays were introduced in the 1950s to make car ride quieter. Undercoating is an asphalt-based substance similar to tar once it’s dry. It’s 10 to 12 mils thick (think 20 sheets of paper) and acts as a barrier against rust and corrosion by sealing out your vehicle’s underside to protect it from the harmful elements of the road.

The procedure involves spraying a black, tar-like substance on the floor pans, wheel wells, and other exposed parts of your car’s underbody, which then hardens and acts as a permanent shield against moisture, salt, and other elements. Unfortunately, over time moisture can seep behind the hard outer seal and corrode the metal beneath. Furthermore, the rigid nature of a tar-based spray makes it susceptible to cracks, which will pose an entrance for water to get in. For those that choose a tar-based spray, yearly inspections are often required to reduce this risk. Ziebart is one of the largest providers of this method of rust protection.

Dripless Oil Spray
Another product, dripless oil, has similar properties to a tar-based spray in that it hardens after being sprayed, creating a moisture seal for your vehicle. Oiling is exactly what it sounds like; it’s an oil-based substance that coats your vehicle’s underside, repelling anything water-based that the road throws to protect it from rust and corrosion. Oil undercoating is extremely thin (think one sheet of paper) and must be reapplied annually to remain effective. It has a firm waxy texture and clings to your vehicle’s frame without any run-off (if very carefully applied).

A dripless oil spray covers more surface area than its tar-based counterpart because it’s applied to more interior regions of the vehicle. Still, this added protection comes with a price. The application process often involves drilling holes into the vehicle’s frame to maximize the area covered. If done by a trained professional, these holes are discreetly drilled and shouldn’t be visible. Additionally, these sprays will often leave smaller crevices, and tight seams on your vehicle unprotected because of their high viscosity. As mentioned, because of the nature of the oil, it does wash off, and it is recommended to be reapplied annually.

How to Prevent Car Rust
My mom said, “An ounce of prevention is worth a pound of cure.”
So how does one go about preventing or mitigating rust if they live in a winter climate?
As you can see, rust on a car can be a very serious issue. This is why learning how to prevent car rust is so essential. Keeping your vehicle rust-free is pretty straightforward. Start with these five tips.

1. Wash Your Car Frequently
One of the easiest ways to prevent rust on a car is to wash it often. Not only will it keep your car looking shiny and new, but it will also remove corrosive debris, salt, and grime. It’s important not to wait for your car to look dirty before washing it. The elements that attack your car’s paint aren’t visible to the naked eye, so by the time you see that you’re due for a wash, some damage has already occurred.

While any car wash is better than not washing your car, a high-pressure cleaner is the most effective. This will allow you to easily clean tricky areas – like your undercarriage and the inside of your wheel arches. For the best protection, plan to wash your vehicle once a week and have it professionally cleaned, waxed, and detailed twice a year.

2. Don’t Forget the Wax
To keep your car in the best possible condition and prevent rust from forming, you’ll want to wax it at least twice a year. This adds another layer of protection between your car’s paint and rust-causing moisture. If you’re not storing your car in a garage, you’ll need to wax it more often to compensate for the extra exposure to the elements. It’s easy to wax your car on your own, but if you don’t have the time, consider adding a hand wax when you take it for professional cleaning.

3. Protect Your Car from the Elements
Constant sun, rain, and snow exposure can do a real number on your car. If you want to avoid rust, you should park it under cover. If your home doesn’t already have a garage, consider adding one. While a heated garage is excellent, the warmth can speed up the chemical reaction of rust, so leaving it outside in the cold is a good idea after all.

Common trouble spots on Rovers, but also applies to almost any vehicle.

5. Repair Rust Before It Spreads
It’s a good idea to give your car a once-over each time you wash it.
Keep an eye out for any paint damage or small spots of rust.

Paint chips are easily touched up with inexpensive factory kits, which are small containers with a little brush inside. Every car owner should have a paint chip kit for their car, and there is no better time to check and correct paint chips than after a car wash.

When checking your vehicle, also pay close attention to the condition of any drain holes, water channels, and seals, especially at the bottom of doors. If moisture collects here, rust can start to form unseen.

Any time you notice a possible sign of rust, it’s essential to keep it from growing. Taking care of it before it spreads can save you time and thousands of dollars in future repairs and greatly improve your vehicle’s resale value!

Need More Help?
Questions, or if we can be of help in any way with service on your Audi, BMW, Land Rover, Mercedes, Mini Cooper, Porsche, or other European import, please contact us. Our team of Service Specialists is here to help, for even the newest autos! (207) 882-9969, or you can email our Service Team at service@atlanticmotorcar.com.

Knowing, not just “doing,” that’s the Atlantic Motorcar Center way.

Warmly,
The Atlantic Motorcar Center Service Team

Case Studies

A Collection of the Odd, Unusual and Interesting Found While Servicing Our Client Vehicles.

Keeping Your Cool – Air Conditioning (A/C) Recharge System Service Process and Costs

Audi, Porsche and VW 2.0 TSI Engines – Rear Main Seal Oil Leaks And Proper Correction

Porsche 911, 912 and 914 – Steering Tie Rod Upgrade Kit – Conversion To Turbo Tie Rods

Bosch CIS (Continuous Injection System) or K-Jetronic Demystified

Porsche 911 – Smoking On Start Up – Q & A And The Why

Porsche Cylinder Bore Scoring – Our Thoughts On This – The Simple Truth

Porsche 911 (Type 991) – Engine Cover Latch Release Problem, and Correction

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