If you own a BMW diesel engine, it’s no secret your vehicle could save you up to 30 percent more fuel consumption than a gas-powered engine.
However, the BMW diesel engine has had its share of criticisms and engine problems ranging from timing chain issues to sticky wastegates.
In this article, we examine 5 BMW diesel problems we have encountered at Fremont Foreign Auto.
- Time chain issue
This issue is most common with N47 engines. These 4-cylinder diesel-powered engines were made with several improvements to replace the M7.
Its timing chain is prone to early wear and tear, which causes it to fail. A symptom of the timing chain failure is a loud rattling sound from the engine. In addition, timing chain failure could cause the engine to fail while in motion.
- Sticky wastegate
It was discovered specific BMW models have a defective return spring on its wastegate, which resulted in early engine failure, as the wastegate is left partially or fully open.
In addition, this problem caused the engines to lose compression and increased fuel consumption by 35 percent.
- Vacuum leak
Over time, the vacuum hose breaks down, causing a leak. Vacuum leaks will not trigger the check engine warning light, although it will throw an error code.
In addition, a leaking vacuum hose will prevent the supply of EGR from bypassing during the warming period of the engine. These stuck EGR builds up in the matrix into solid particles and may escape into the intake tube, causing holes and leaks, which may cause a fire.
- Air mass sensor failure
Your BMW has its MAF located within the intake system and is responsible for monitoring the amount of air sucked into the engine.
Bad MAF is a common problem. Symptoms include engine stalling or jerking during acceleration, black exhaust smoke, loss of power, and misfires. To fix this issue, you will have to replace your vehicle’s faulty air mass sensor.
- Coolant leak
Coolant leaks are a notorious problem of the BMW diesel engines, especially the older versions.
The coolant acts as a temperature regulator in the diesel engine, and leaks could cause the engine to overheat. Overheating is catastrophic to other engine components. Some common causes of a coolant leak include a damaged radiator, leaking hose attachment, blown gasket head, cracked tank, and more. The remedy is to replace the damaged components responsible for the leak.
If you notice any of these problems on your BMW, don’t hesitate to contact our experts to diagnose and fix the problems before they escalate.
At Fremont Foreign Auto, we are experts at BMW vehicles and know how to fix all diesel-associated problems. Call us at 510-793-6067 to get a quote and book an appointment.