Originally posted by inspector1
A wiring harness is an extreme long shot for a random misfire code. If the harness was bad, one would have other symtoms.
Advise given above is good.
When my harness went bad, random fault codes, including misfire codes, was all I had. Eventually the problem gets worse, including hesitation, popping (backfiring through the intake manifold), missing at idle, etc.
Enrique at MB Motors tells me that random codes are always the first symptom of a failing engine wiring harness.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".