Best of luck. The misfire code is not very specific so when I had the same thing the dealer started with the smoke test etc. Ironically I got it only on really hot summer days.

After replacing all of the gaskets and not solving the problem we tracked it donw to the AC compressor failing and vibrating such that the engine computer thought the engine was misfiring. (Very rare I am sure.)

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2013 X5 xDrive3.5i Premium
2002 530I Sport Package
2001 X5 4.4i
2001 M3