Q: Car rough idles and worse when engine is warm - 2008 BMW 528i

asked by on September 21, 2016

My car has a very rough idle. It has approximately 87,000 miles on it. A decarb has already been performed. When the engine is warm and the car is not in motion (just sitting) is when the rough idling problem is the most noticeable. There is a dip in the idle, but my car does not die. Could you please tell me what is causing this so that I can fix it. Thanks.

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Hey there. You should first check for any problem codes. Next, check for vacuum leaks. Third, check out the idle air control valve - clean it if possible. A professional mechanic, like one from YourMechanic, can help with this diagnosis and repair of your idling issue.

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