Originally Posted by
Padgett
That would be a good answer if it was a Mercedes and not a Chrysler ECU (which may have needed tweaking to meet US specs).
The engineering answer is to bypass the spark plug on "#3" and see what code sets.
Wow.....that answer is scary wrong. A OBDII compliance means exactly that. The ECU is compliant to communication with the scan tool software.
YOU should know that if you are giving answers and advice here.