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Tech Blog
Discussions About Common Car Problems



BMW S85 Valve Spring Failure and Repair. 2006-2010 M5/M6

Valve spring failures on early production run (2006-2007 model year) S85 engines have been pretty well documented. These defects were quite common and would usually happen at fairly low mileage (generally under 20,000 miles). Since the cars were new and under warranty BMW warrantied quite a few valve spring jobs, so much so that they redesigned the springs for the 2008 model year. Although the new design was a drastic improvement from the previous, the issue was still far from "ironed out". This is my project of repairing the extensive damage from a cylinder #1 intake valve spring failure on my 2009 BMW M5 with 91,000 miles. I was driving to the beach with my dogs on a Sunday afternoon, making a left on 2nd St in Long Beach, I tap the SMG into 2nd at about 25 mph (luckily I wasn't going very fast) and with no noise at all the MIL lights up with the "reduced power" warning on the iDrive and I immediately feel a misfire. Given that it happened so un-dramatically I assumed that I probably just had a bad ignition coil. I pulled over and got the car towed to my shop. So I begin diagnosing the problem and upon removal of the valve cover, and later the cylinder head itself this is what I found.


Intake Valve Carbon Buildup on Direct Injection Engines

A very common problem that has recently been plaguing direct injected BMW's, Mini's, and VW/Audi's has been the buildup of carbon deposits on the back of the engine's intake valves. This usually manifests itself as a drivability complaint such as rough/irregular idle (especially when cold), a check engine light being illuminated (usually with multiple cylinder misfire fault codes stored) or a failed smog check due to high HC's. The most frustrating part for owners of these cars is that these problems can be seen on an engine with as little as 40,000 miles! What causes this buildup is that a direct injected engine injects fuel directly in the combustion chamber as oppose to a conventional engine where fuel is added somewhere in the intake port which allows for the gasoline to literally wash the valves before it enters the combustion chamber, overtime the carbon buildup to the point where the driver notices that something's not right. Luckily there is a far cheaper alternative to the dealerships $1,400+ cost of removing these deposits which are generally not covered under warranty. At First Class Autoworks we begin by first removing the intake manifold to see how extensive the buildup is to determine how much cleaning time will be needed then we proceed to "pre-clean" the valves with a metal pick and wire brush to remove the large chunks of carbon, then we proceed to applying and "abrasive blasting" that removes ALL of the deposits on that valves and restores them to a like-new condition. These repairs can be performed in one day and with pricing varying with number of cylinders, engine arrangement, and amount of carbon buildup. Have further question? Call us at 714-773-5500.


Mercedes-Benz ESP/BAS Malfunctions

Mercedes-Benz ESP/BAS Malfunctions

ESP and BAS are two innovations pioneered by Mercedes-Benz. They are essentially cutting-edge forms of electronic traction control that use the inputs of various sensors monitoring events such as individual wheel speed, yaw rate, steering angle, throttle demand, and pressure applied to the brake pedal.

These inputs are processed by the ESP module which can intervene by reducing engine output and increasing or decreasing braking at individual wheels to keep keep the vehicle stable and prevent it from spinning out of control.

So what does it mean when you see a "ESP/BAS Malfunction" warning light illuminated on your car?

It means that the on-board diagnostics have detected a fault somewhere in the ESP system, the system is disabled and cannot assist in a low traction situation or evasive maneuver. This can be caused from faults within the ESP system itself or even those in other control modules that share the same CAN communication line such as the ME (Motor Electronics) or ETC (Electronic Transmission Control) modules.

These systems are extremely complicated and should only serviced by properly trained technicians experienced in the diagnosis and repair of systems. If you're experiencing problems like this with your Mercedes, feel free to give us a call anytime at (714) 773-5500.


BMW Brake Fluid Service

What does this mean?

If you drive a late model BMW equipped with iDrive, chances are you have encountered the "Brake Fluid Service Due" message on your iDrive screen and wondered "what does this mean?" We get this question quite a bit, so this would be a good opportunity to explain what this means. A BMW brake fluid service is essentially a "brake flush", meaning a machine is hooked up to the car (via brake master cylinder and fittings at each wheel) that simultaneously pumps brand new brake fluid into the cars braking systems while it evacuates the old dirty fluid into a waste tank. The end result being 100% brake fluid replacement as oppose to just changing out the fluid in the master cylinder, which would only result in approximately 40% of the brake fluid replaced leaving the brake calipers and lines full of the old fluid.

Why does my BMW need this service?

Brake fluid is considered a hydroscopic fluid, meaning it absorbs moisture. The braking system of a modern BMW contains quite a bit of electronic computer controlled components such as DSC/ABS modules and electronic parking brakes and as with all electronic components they are sensitive to moisture. Over time the brake fluid in your car absorbs moisture and this combined with the repeated exposure to high temperatures lowers the boiling point of the brake fluid. Performing regular brake fluid services helps keep your braking system moisture and contaminant free.

How often is this done?

BMW recommends that you service your cars brake fluid every 2 years regardless of mileage. Doing so will ensure that your vehicles brakes perform as designed and helps preserve the internal electronic components of your braking system.

Feel free to contact us anytime at (714) 773-5500 with further questions about your BMW.


VW/Audi TDI Service and Repair

Turbocharged Direct Injection or TDI is a design of turbodiesel engines, which feature turbocharging and cylinder-direct fuel injection developed and produced by Volkswagen Audi Group (VAG) to meet the demand for higher MPG ratings. Although passenger cars with turbo diesel engine are relatively new to the US market, they have been the popular choice in Europe for quite some time. Naturally first time diesel owners would have some questions about their cars service needs. Here are a few common questions we are asked:

How often should I change my oil?

TDI VW and Audi are equipped with the same on board maintenance reminders and follow very similar maintenance schedules with the addition of 20,000 mile fuel filter change intervals, 40,000 mile DSG transmission service and their requirement for top tier fuel which is also true of gasoline direct injection engines. On board service reminders displayed on your gauge cluster or MMI interface will let you know its time for a service. Engine oil type must be certified with VW/Audi approval 502 00/505 00/505 01.

Does my TDI cost more to maintain than a gas engine?

TDI's do have a slightly higher maintenance cost than gasoline engine's, but this difference is offset by the TDI's outstanding fuel economy. Like any internal combustion engine the key to avoiding costly break downs is preventative maintenance, regular fluid and filter changes play a vital part in an engine's reliability.

Have any further questions about your TDI? Feel free to contact us anytime at (714) 773-5500


Land Rover Air Suspension Problems and Repair.

Land Rover is famous for their sophisticated air suspension systems which can be found on the Range Rover, Range Rover Sport, LR3 and LR4 models. These systems are known for their ability to change their supple ride while on the road to a much firmer and higher ground clearance in the "Off-Road" setting , all of these changes are made by the turn of the mode selection knob by the driver. The system can also be set to a low-height "Access Mode" to facilitate getting in and out of the car.

These systems, although very rugged, are not without their problems(although not nearly problematic as many believe). Depending on the mileage and model of your Rover your vehicle may be prone to different problems. For example, most Land Rover air compressors are fairly well designed units that last well past the 100,000 mile mark, as oppose to earlier Range Rover Sport and LR3 models that came equipped with rather small compressor that was prone to overheating. Land Rover has since re-designed this unit and now offers and updated more robust compressor to address this problem.

Moving on to the air shock - the air shock's on all Land Rovers are well built units that generally will start to leak after the 100,000 mile mark. A common sign of a air shock leak would be one corner or the vehicle sitting much lower than the rest, when it is time to replace air shocks, some customers opt to convert their Rovers to a conventional shock/spring assembly. This conversion does save substantially on cost, but it does, however, change the ride quality and you lose the height adjustment feature of the air suspension.

If you have any further question regarding Land Rover air suspension, feel free to call us at (714) 773–5500.


How Often Should I Service The Transmission In My Mercedes-Benz?

This is a question that we get quite often from Mercedes-Benz owners. The proper service interval for your transmission can vary depending on the year model of your Mercedes.

The two main transmission types found in late model Mercedes-Benz vehicles are the 7G-Tronic (designation 722.9) and the 5G-Tronic (designation 722.6). The 5G-Tronic is the older 5 speed transmission that was first introduced in the 1996 model year S Class, the 5G-Tronic has a service interval of 100,000 miles. At this mileage the transmission should be service by changing the transmission fluid and internal filter located inside the transmission pan.

The newer 7 speed 7G-Tronic transmission was introduced in the 2003 model year to keep up with stringent fuel economy requirements. The service interval on the 7G-Tronic is usually between 40,000-50,000 miles it is serviced in the same manner as the 5G-Tronic by changing the fluid and internal filter. Neither of these transmissions are equipped with a dipstick to check the fluid at home, and must be taken in to a repair shop properly equipped to service these transmissions to check and top off the fluid correctly.

If you have any further question regarding the transmission on your Mercedes-Benz feel free to call us at (714) 773–5500.


What kind of oil does my BMW require?

This is a question that we hear quite often from our customers. When performing a BMW oil change it is very crucial to use not only use the correct weight (5W-30, 10w-40, 10W-60, etc) but the oil must also carry a specific BMW approved rating. Depending on the year of your BMW this can be a BMW Longlife 98, BMW Longlife 01, or BMW Longlife 04 rating. The reason for this rating is to ensure that the oil can stand up to long oil change intervals that are required on all late model BMW's. At First Class Autoworks we insist on using only the highest quality BMW approved full synthetic motor oil. That is why we stock engine oil from Germany's #1 oil company: Liqui Moly. You can always count on First Class Autoworks to use the ultimate parts for your ultimate driving machine. For excellent quality and service, give us a call at (714) 773–5500.

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BMW Electric Water Pump Failure –

BMW introduced the electric water pump in the 2006 model year in all inline 6 engines (engine codes N52/N54) commonly found in the 3 series (E90), 5 series (E60), Z4 (E86) , X3 and X5 chassis. The electric water pump was designed to reduced drag on the engine to increase power output and fuel economy, but it is not a perfect system. These water pumps generally fail in the 50,000-80,000 mile range, symptoms of a malfunction with your cars water pump can include the check engine light/service engine soon light being illuminated on your dash, cooling fans running all the time, and as well as any engine overheat warnings that may appear on the dash or iDrive. If you notice any of these symptoms we advise you to find a safe place to pull over and shut off your engine to prevent further damage to your engine and give us a call at (714) 773–5500.

Here is a list of cars that are equipped with electric water pumps: 2006-2013 model year BMW 128i, 135i, 323i, 328i, 330i, 335i, 525i, 528i, 530i, 535i, X3, X5, and Z4