BMW (Bayerische Motoren Werke)
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Maintenance/Service

​Previous Inspection I (minor) and Inspection II (major) have been replaced by BMW with CBS (condition based service)  type of maintenance services, thus enabling BMW to better monitor and alert wear of individual components or systems. 

Be observant of exclamation signs in your instrument cluster and other warnings/telltales as they signal either issues or services due. Always consult your service manual if unsure of what they mean. Never drive for longer distances with a flashing check engine light.

Often times neglected maintenance items can lead to expensive repairs. One such example is spark plugs worn out that can lead to ignition coil failure that can lead to catalytic converter failure or transfer case/transmission fluids. Although BMW is not explicitly recommending an interval for transfer case, differential and transmission fluid service, we are routinely finding messages in the vehicle's control modules prompting the replacing of fluids in the transfer case or transmission. 

There is not a fluid that will last a lifetime in a vehicle, not even the washer fluid. BMW is using he lifetime fluids approach to ease concerns with high maintenance costs; that will be a factor for some when considering buying a BMW.  Transmission failures along with transfer cases and differentials tell a different story, and the repairs are usually very costly.

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Spark plug replacement

One of the most common maintenance service and also essential to have done in time because if neglected it can lead to major issues, misfires, further damage to the catalytic converters and ultimately you can end up on the back of a tow truck. Usually done around the 100,000km mark, the first signs of excessive spark plug wear is a rough idle running especially at startup in cold weather. Initially it will not trigger any engine light faults but if ignored it will lead to misfire and possibly reduced engine output. We only use OEM original spark plugs, NGK or Bosch, depending on BMW recommendation.

 

​Air filter and cabin filter replacement

The air and cabin filters are replaced usually between 30,000km and 50,000km depending on the condition. Excessive clogging of the air filter will lead to reduced performance and fuel economy, and if really bad will trigger an engine light. It should be checked every two years or 30,000km. 

The cabin filter is responsible for filtering the air inside the car as the name suggests. Some BMWs have two cabin filters, one also called a dust filter or pre-filter. Neglect can lead to reduced air flow at the vents, extra strain on the blower motor and sometimes foul smell in the cabin. Most cabin filer are charcoal  activated, meaning they are efficiently filtering out the carbon monoxide coming from the surrounding vehicles. Purflux, Mann, Mahle and Hengst are our preffered OEM brands for filters.

Brake service

Under normal condition, the brakes will last somewhere between 40,000km and 60.000km. BMW has implemented one of the most advanced brake wear monitoring system, with sensors that will inform the gradual wear and approximated life time remaining. This is easily accessed through the iDrive menu, under Vehicle Information. When the pads are worn out there will be either an exclamation mark in the instrument cluster for the older models, or a message in the iDrive display, informing the driver that the brakes will need servicing.

There will be a grace time period from the time the brake warning is set which gives you about a month or so before the brakes pads' lining will completely wear off. If you hear a grinding noise while applying the brakes, that means that you have exceeded the grace time period to service your brakes. It is UNSAFE to drive with grinding brakes as this will quickly overheat the brake fluid which can and WILL lead to a total loss of brake ability due to vapors in the brake system. It's best to have your vehicle towed to the repair facility when you experience brake grinding noise.

When servicing the brakes it is imperative that the rotors will be replaced along with the pads/sensors. The rotors wear down just like the pads and will become thinner, their face will sometimes become scored, hot spotted or rust pitted. We can install just pads at your request but we shall be liable free of any brake noise, brake pedal pulsation, performance and premature wear (voids warranty).

Ontario's excessive salt conditioning of the roads in the cold weather leads to premature wear of the brakes and for prolonged life we recommend a service every two years even if your brake pads aren't worn out. This is especially useful with vehicles that are driven under 10,000km a year. This service entails removing of all the brake pads and rotors and cleaning off the brake pads' brackets (usually a lot of rust), wheels' hubs, lubricate everything and putting everything back together. This includes servicing the parking brake, cleaning of the adjuster and shoes' contact points, and finally adjusting the parking brake. This is the same service we provide when we replace the worn out brakes but without the parts.

The road salt and the rust that it causes can prevent the pads sliding in their brackets, can seize up the calipers' sliders or the parking brake adjuster, shoes and/or cam mechanism. All of these conditions will lead to uneven and premature wear and degradation of braking performance. We use OEM top of the line parts like Brembo, ATE, TRW, Textar, and Zimmerman just to name a few of the brands. Upon completion, the brake monitoring system will have to be reset.

Cleaning and lubricating the brake pads' bracket is essential. Here we use copper spray on the contact points. This provides lubrication and prevents rust formation (pic above).

​Brake fluid flush

Brake fluid flush is recommended to be done every two years, and that applies to all European vehicles. BMW will trigger a service message when brake fluid is due, and will have to be reset upon service completion.

Due to its chemical nature, brake fluid attracts moisture (hygroscopy) and the fluid's reservoir is not fully sealed, thus contaminating the fluid over time. Moisture will also lead to the corrosion of the brake lines and an very old fluid, the color is changed to dark brown indicating advance contamination.

The presence of moisture not only causes wear in the brake system (calipers, cylinders and the ABS pump/valves) but it also lowers the boiling point, making the brakes more susceptible to fail under heavy braking condition (brake fade). 

It's a relatively inexpensive service and when combined with an oil service it's even less costly. 

Brake fluid flush using industrial brake bleeder. Pressure is being applied to the master cylinder, pushing all the fluid out in a timely manner.

Transmission, transfer case, differential service

Even though BMW claims that transmission, transfer case and differential oil will last a lifetime, anyone with technical common sense knows that is simply not true. All fluids in a vehicle change and wear overtime, the transmission, t-case and diff's oils even more so given the harsh environment these oils operate in. Mercedes and pretty much all other German brands specify a replacement interval for these fluids and our recommendations are as listed below:

• transmission fluid and filter - 150,000km or more, unless transmission shifting is harsh or BMW own's on board diagnostic prompts for a service (will show up on a transmission module scan).
• transfer case fluid - 200,000km or more, unless t-case exhibits abnormal behavior or BMW own's OBD prompts for a service (will show up on a scan)
• front and rear differential - 250,000km or more, unless diff is noisy ore exhibits abnormal operation (shudders in turns, noisy).

The valve body, torque converter, gears, fluids, all wear down over time and fresh lubricant will prolong the life of your transmission, transfer case or differential. Waiting for transmission, transfer case or diff problems to happen will usually lead to expensive repairs and long downtimes. 

Pictures above show differential, transmission and transfer case services being performed in our shop.

Convertible top service and repair

We diagnose and repair convertible tops and sunroofs. The electrical and hydraulic parts only, we don't do fabric repairs. The Z4 is infamous for its common el. motor failure, usually caused by debris clogging the drain in the conv. top motor's enclosure. This usually fries the el. motor and the replacement is both, time consuming and expensive. We offer relocation of the convertible top motor, away from the its usual spot and inside the trunk, thus preventive future failures (extra cost). The 335's hard top should be periodically serviced (lubricated) to prevent premature failure; same goes for sunroofs and soft tops.

Last image shows how the convertible top motor gets soaked in water due clogging of the drain hole. Most Z4-s suffer from this issue.

In the images above (last two pics) you can see the relocation of the conv. top motor, away from the water drain for avoiding future failure.

 

                    Common BMW-s failures


Oil leaks

Older BMW-s or high mileage engines have a reputation for leaking oil. Not a matter of if but a matter of when. Usually most BMW-s will start developing oil leaks at around the 150,000km mark. Some sooner, some later but almost none is immune to this issue, and it's just a wear and tear problem. Well, one can argue that 150,000km is too soon for these problems to develop but age, the use of plastics, heat and sometimes a lack of maintenance will cause this annoying issue, ruining driveway and driving owners crazy with the costs of repairs. Below are some of the common oil leaks on some of the most common engines (N20, M54/N54, N52, N55, M62/N62/S62).

Valve cover 
When the valve cover starts to leak (and they all will at some point) it will cause a mess. In the later stages, smoke will start coming out of the engine bay, sometimes ending up in the cabin through the ventilation system; this is caused by the oil dripping on the hot exhaust system. It can also build up in the spark plugs wells, damaging the coil on plugs and causing misfires. 

We don't recommend replacing just the gasket as the plastic valve cover will most likely start leaking again. Being made of plastic, it can crack upon disassembly, will end up warped from the excessive heat or the crankshaft ventilation system of valves that is built is damaged. We can replace just the gaskets if you insist but we cannot warranty the job for those mentioned reasons.

This would be the ideal time to also replace the spark plugs since it takes only an additional half hour of labor.

The image in the middle shows the oil around the ignition coils and the potential damage caused by a leaky valve cover. Always a good idea to replace the spark plugs (last image) when doing a valve cover as the labor is minimal.

Oil filter housing and cooler gaskets

Unlike the valve cover, a leaky oil filter housing or cooler gaskets, if left unattended, will lead to the contamination of the rubber in the serpentine belt and radiator hoses. Countless engines have been destroyed by this failure alone. Oil will damage the belt, in turn the belt comes off and ends up wrapped around the crank pulley; from there it is pushed inside the crankcase, and finally, the oil pump strainer gets clogged by the rubber. The result is oil starvation end engine damage, usually unrepairable due to high costs. 

Inexperienced mechanics or rushed jobs fail to properly asses the fallout of a broken drive belt and just replace the belt. Meanwhile, the front seal is damaged and belt remnants will lead to engine destruction days later. 

Radiator hoses get damaged by oil also and end up bursting, causing damage, sometimes very costly due to the loss of coolant. The oil filter housing/cooler gaskets is not a job that should be neglected!

Oil cooler gasket and oil filter housing gasket and at the right, the two gaskets that harden up with time causing leaks.

​Engine oil pan gasket 
Also a matter of time, this labor intensive gasket replacement is the cause of many ruined driveways. The loss of oil and running an engine with low oil level is also not conducive to long term reliability. 

Front main seal 

Not as common as the other gaskets but common enough, the front main seal (crankshaft seal) can leak and be confused with an oil pan leak. Replacement is not that straightforward and it require a special puller and installer tools to do it correctly since the seal is extra wide and impossible to remove without proper tools. If ignored, this leak will contaminate and lead to the drive belt failure and potentially major engine problems.

In the images above, the oil contaminated belt came off and wrapped around the crank pulley damaging the front main seal and breaking one of the VANOS solenoids in the process (last pic). A lot of belt got pushed in the engine and it has to be completely removed or else engine damage will occur. 

VANOS and Valvetronic faults


BMW-s variable timing (VANOS) and variable valve lift (Valvetronic) are running on a clean supply of engine oil. Contaminated or low oil is the lead cause of VANOS/Valvetronic failures. From solenoids to intermediate levers to worn camshaft.  Use only BMW approved, high quality oil and top up your oil as soon as the vehicle prompts you to do so and we also recommend switching to 10,000km oil change intervals in order to prevent issues with these two systems. 

Poor oil quality, crankcase breathing problems, worn out oil or low oil will contribute to abnormal operation and failure of the VANOS and Valvetronic systems. The most common failure is VANOS solenoids getting clogged up (see pics below), wear on the Valvetronics' intermediate levers and camshafts, oil contamination of the Valvetronic eccentric shaft position sensor, carbon build up on the intake ports and valves, electrical faults, etc.

Having the proper diagnostic tools and more importantly the knowledge and experience to tackle these complex systems is essential in providing a correct and efficient diagnosis. Our technicians are regularly sent to BMW specific training courses to keep up with the BMW new technology and engines.

Eccentric shaft sensor being replaced in the first pic, clogged up VANOS solenoid and valvetronic repair in the last picture.

Water pump and thermostat

E series and F series BMW-s were equipped with electric water pumps. The radiator fan running constantly at high speed is a sign that your cooling system has a problem and the water pump is one of the most common failures. Electric water pumps enable precise volume adjustment and control as opposed to the mechanical pumps that run continuously.

​This precise thermal management is not only ideal for the engine's operating conditions but enables significant fuel economy. Usually reliable up to 150,000km or more, the electric water pumps and thermostats will wear out and can cause an overheating condition. Replacing a failed water pump is best paired with a new thermostat as well, since the labor for the thermostat will be free, as it's being removed during water pump replacement. 

​OEM parts are exclusively used at German Automotive and prices are still well below dealer while warranty is still the same, two years! To the right, we are replacing the electric water pump and the thermostat on an E series BMW. Behr and Pierburg are two top OEM parts suppliers that supply BMW as well but we are able to get big discounts by ordering through our Euro specialized suppliers.

 

​Engine misfires

The dreaded engine light caused by misfires can be 75% eliminated by replacing the spark plugs every 100,000km. The other 25% of engine misfires are caused by failing ignition coils, faulty/worn out injectors, intake carbon build up and air leaks/lean conditions.

While replacing the spark plugs can be straightforward although challenging on the V8 engines, the injector diagnostic and replacement is a different matter altogether. Specialized equipment and expertise is needed when dealing with problematic fuel injectors. They can be seized up in the cylinder heads requiring pullers and patience but they also need careful programming to match individual injectors characteristics with the engine management. 

First pic: worn out plug vs new spark plug, note the gap difference. Replacing injectors in the next pic and lastly finding an air leak by pressurizing smoke.

Coolant/Antifreeze leaks

Coolant leaks are unfortunately all too common due to the use of plastic in the cooling system or from coolant hoses damaged by oil. The expansion tank, parts of the radiator, the thermostat, and parts of the hoses are made of plastic. Over time the plastic ages and coupled with the high heat in the engine bay it leads to degradation. Plastic will crack either by itself or during a disassembly process. The loss of coolant can lead to severe engine damage due to overheating if not dealt with it immediately. 

It's very common to have a "low coolant" warning showing up in the instrument cluster right when the weather turns cold. This is due to the gradual coolant losses due to evaporation/permeability and the contraction of the coolant coinciding with temperatures drop. It's a good idea to top up your coolant the moment you see the message and if any leaks are noticed on the outside (drippings) you should take the car to the repair shop without delay. 

Expansion tanks are common to crack, vent lines, radiators and radiator hoses crack as well in time, and oil contaminated coolant hoses will swell and eventually burst. We usually check for rad. hoses' swelling during the routine maintenance inspections. The older M54 engines had the crossover pipe (under the intake manifold) leaking due to the use of plastic piping, the V8 (M62/N62) engines had the coolant crossover pipe and rear coolant covers leak, the N63 had issues with the turbocharger cooling hoses and the newer engines (B48/B58) have issues with the oil filter housing/cooler, again, due to the use of plastic. 

M62 crossover pipe being replaced, new N63 turbo cooling lines in the middle and lastly, a cylinder head being replaced on an overheated M54 engine.