Sounds fairly similar to what my '94 Z28 has been doing. Try cleaning the mass air flow sensor. Just go to any auto parts store and get MAF cleaner (that's actually what it's called) and take the MAF off and spray it. Just don't touch the wires in there. That made my car run quite a bit better. Just a guess though. Don't hold me to it.

 

I am having a similar problem and can't get it to run good enough to make the trip to get the codes read. New plugs, new wires, new EGR valve. Idles fine for a few minutes, then misfires. Put it in drive and it misfires so bad it will barely pull itself. Sounds like it is out of time! Checked resistance on coil packs and they show good. Test resistance on injectors and they show good. Need to check regulator pressure but have not done that yet.

 

Hey, osduck, that sounds like my exact problem. If you figure it out I would appreciate it very much if you would tell me what it is.

 

Will do! I am either going to buy a code scanner or try to rent one somewhere so I can see what might be wrong, otherwise, I will be chasing my tail. From what I have been reading online, I am leaning towards coil packs. I used a known good plug wire and plug, attached to the coil packs and on 2 of the 3, I am getting a yellow spark instead of the blue spark that I would think needs to be there to have total combustion in the cylinder.

 

I just returned home from working on car. I replaced all 3 coil packs, fuel filter and car still run like it was out of time, wouldn't even pull itself. I knew I had fuel on the rail and all injectors were clicking. I replaced the cam position sensor with the one that was on the blown engine. Donor engine fired up and hasn't misfired yet. I drove it about 30 miles just to see how it run. SES light is still on but now at least it runs and I can drive it over to get the codes pulled. I know 30 miles is not alot but hopefully, the misfire issue is gone for now. At this point, I don't know if I fixed it or if I just got lucky!

 

My 3.4 was doing the same thing. It turned out to be a bad plug wire. I changed the plugs first and did not find it. Plug 1 runs past a vertical section of the exhaust manifold. The plastic protection sleeve had melted and was holding the plug wire together! I found it when I replaced the wires. Believe it or not, this caused all the same symptoms described in this thread.

 

Thanks for the advice guys. I think I'll try the plug wires first. If that doesnt work I'll see if I can do anything osduck did.

 

Good luck! We have almost 300 miles on it since that post and still running without misfires.