When I am at a red light with the lever on Drive position, there is a vibration in the car body. I did some experimenting and found that if I slightly increase the engine speed while holding the brakes, the vibration disappears. So I asked the auto repair shop to do it - to increase idle speed of the engine. They told me that the car is pre-programmed and that they couldn’t do anything there. Can you explain this to me please and tell me how I can get my car fixed? Thank you.
The idle on your 2006 BMW 545i is automatically set by the computer, and if your idle is not within specifications, then you can have the throttle body and idle air valve cleaned. The motor and transmission mounts should be checked to see if they are sagging or broken. The base idle is set by the throttle plates, and the computer idle is set by the computer program and neither is adjustable. Cleaning the throttle plates and air valve will raise the idle some and may help along with cleaning the induction and injection system will help idle smooth out. If you want to have this checked, a certified technician from YourMechanic can come to your car’s location to diagnose your rough idling issue and assist with a repair.
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