Can't find cause of misfire F10 N55


Feb 19, 2020
So it started with misfire on #3...found #3 spark plug wire not fully on plug. Ok for a short test, then got it on multiple cylinders, mostly just #4 if I bring boost up slowly.

Reset adaptations vanos, throttle body and cause an error 164040 Intake cam installation error. I can get this to go away, except for a moment if I let the car sit on for at least 30seconds before starting. Puts me in limp mode and the car doesn't boost. I can floor the car (much less power) and the car doesn't misfire.

If i get the 164040 to clear and starts to stumble and misfire on multiple cylinders...sometimes going back into 164040 error, sometimes not.

Changed spark plugs and gaps...same, swapped and replaced Precision Raceworks coils..same, replace all injectors (#4 had a small amount of blow by...same. Removed and cleaned vanos solenoids, then even replace the intake one...same. o-ring on oil filter tip...same. Checked vanos bolt heads...all good and tight.

Ran ISTA+ Vanos cycling 450 times all good...tested eccentric shaft good.

Can someone tell me if they see something I don't in this MHD log?


  • 2023-09-05 06_08_06 00000FEF81A001 v1.07 ps2 95_102.csv
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