Good afternoon everyone. A few months ago I replaced everything for the ignition(94 Z28 LT1)
. Plugs, wires, cap, rotor, distributor, optic eye, coil, ignition module. Everything was running great, until a few weeks ago. It started having a mild missfire, only after I started it up after 10 to 20 minutes of it eunning. It would choke up, but then it would clear up after just a couple minutes and drive fine. But now, oh man..... it's a constant hard missfire. However, at WOT or almost WOT it runs fantastic, actually runs like it should. If set my cruise I have to blip the throttle every 5 or 10 seconds so it's not misfiring. Would I be wrong to think maybe my MAF sensor is to blame? Or a TPS? I have spark on all 8 cylinders.
*Update* A new symptom to go with my current situation. Service engine soon light comes on, car runs perfect. Engine light goes off, back to running with a massive missfire

 

When my '93 did the same thing after a tune up it was a burned plug wire on number 8,hardest one to get to of course.

 

Thanks. I'll take a look at my wires. Would be sweet if that was the problem.

 

Good luck with it.

 

So here's a true story. Took my Camaro out of town because every now and then you just feel like letting her rip Tater chip. Did a massive brake stand burnout and then drove the Camaro for another hour after that, I have no running issues at all. Drove it again the next day ended up driving it for two-and-a-half 3 hours, no running issues at all! Cars are strange like that sometimes. After frustrations of trying to track down my running issue and now it just runs fine? I still have no doubt in my mind that there is still something wrong. Is it possible I have spark Arc going on with my wires and I just knocked them apart doing a burnout?

 

Certainly possible,mine would come and go like that until the wire completely fried.

 

So, did your wire fry from exhaust heat or from arcing?

 

I believe it was arcing but I had a mechanic replace it under warranty as he had recently done a full tune up on it so I'm not 100% sure.