Originally Posted by DriftMGR
Cold Misfire 96 Taurus GL 3.0L / Just had cyl. Heads Reman. On cold start only / throws a cyl. 6 misfire code. When erased when warm, no code given. Replaced wires to no avail. Car seems to run fine / but throws codes. Gets an occasional 52 for airbags / when reset is fine for weeks, then mysteriously reappears. Only other codes are the 420 and 430 for the cats (Ca. Vehicle) and these are very infrequent. Car is smogged, but I'm sure it could benefit from the new cats, but the cost factor for Cali emission is high.
For the catalytic converter efficiency codes (P0420 and P0430) I would try 2 new Downstream O2 sensors (after cats.) first. Aged Downstream O2 sensors can have slightly out of range readings causing the Catalyst OBDII Monitors to falsely fail and set a code.
Cylinder #6 Misfire (P0306). Front bank far left cylinder. Have you checked the spark plug yet??? have you tried swapping the #5 and #6 fuel injectors yet???