Q: Engine seemed to be running too rich or too lean, not sure which.

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Car is running very rough when you step on the gas. It seems like the engine is either starved for gas or air. The Check Engine light is also on.

Many different problems can cause an engine to run rough and lack power. The first step is to retrieve the diagnostic code associated with the check engine light. This will provide a general idea of where to begin the diagnostic process. BMW vehicles often have problems with their VANOS variable valve timing systems. A skilled technician, such as one from YourMechanic, will be able to tell you if this or something else is cause of your symptoms.

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