MY '90 3.0 4WD Mighty Max has been throwing a Check Engine light for about 6 months now, and when it first came on I had a friend with an OBD1 scanner read the truck and it said it was throwing a misfire on cylinder #1. I changed the plugs and wires as a start, which they heeded to be changed anyway, and we reread it. Still throwing the misfire code. I tried changing the distributor with a rebiult unit along with a new coil. Still got the code. I changed the MAF off the parts truck out back, put a new oxygen sensor in it, changed the fuel filter, I ran SeaFoam through it twice, and changed the plugs again, and it is still telling me it is misfiring, and now the idle quality is complete garbage. I am starting to think either the previously rebuilt ECU is going bad again, or the wiring harness itself is going bad, because I am seriously starting to run out of things that have not already been changed in pursuit of this darned code. Another clue giving me that thought is the radio reception has always had static in it through 3 differnet radios and 2 antennas, so I'm thinking the harness might be shorting out somewhere ? Idunno. Anybody else got any ideas or suggestion on what else to look for. I'm starting to lose sanity on this truck. Help ?
Things replaced in past 6 months while light is on :
The truck is laughing at me now, I can hear it out in the driveway snickering