2003 X5 3.0i w/82K miles. Runs great. Started today after sitting in basement garage for three days. Check engine soon light came on and idle was terrible. Drove to close-by car wash and then home. Felt like running on four cylinders only; very rough and zero power. The higher the RPM's the worse the engine vibration.

Pulled into garage, turned key off, restarted and ZERO issues now. Runs like before--just about perfect. Wonder why I got a check engine soon light? Now it runs fine.

The funny thing is that I'm trading it tomorrow as I made the deal right before Christmas and they needed to get the new car ready. Was my X5 just pissed at me or what????