I finished up the heads/cam install a few weeks ago and since then I've been fighting a very bad high rpm miss. It pulls good till 6000 or so, then just starts violently popping, stuttering, missing..etc, it kinda feels like a rev limiter, it completely stops pulling altogether. My rev limiter is set at 6600 though, so its no where near hitting it. My friends said they saw flames shooting out the exhaust when it was missing, if that helps. I saw my wires arching at night, so I re-routed them, to no avail. I also put new plugs in, still the same miss. I also installed a new walbro 255, also to no avail. Before I did the heads/cam install, it used to do this intermittingly, prolly once every 7 times I went WOT. I figured it was the opti on its way out, so I upgraded to the vented opti when I did the heads/cam setup. Now it has the high rpm miss EVERY time 3 things I can think of: The coil. Do they go out often on these cars? Would it cause a severe high rpm miss like this? Maybe another bad opti? Or could it be that the programming is maybe a little off (Alvin at pcmforless.com did it, its kinda hard to get the perfect tune on the first try, ya know) THANKS GUYS!!

 

My very good friend's john is having the exact same problem.... we are about to swap plugs and wires????? we need to know what this might be aswell???
thanks to anyone who can help up!!!
Steve

 

Are you still using the stock coil and coil wire?

 

He's on the right track

 

I am with the above, replace the coil and wire and see what happens.

 

I've got the same problem.. And I even bought a nifty MSD coil. Still does it.

Gonna swap out plug wires and see if that'll fix it

 

Cool, thanks guys, I'll go buy a new coil. Should I just get an AC delco coil? I still have the original coil right now, but I have a taylor coil wire. 1 question though: Is a coil wire any different from a regular spark plug wire? I replaced my stock coil wire with a short spark plug wire...I hope coil wires are the same thing as spark plug wires...

 

My IROC does this when using a 150+ shot of nitrous. If you figure it out lemme know.

 

Definitely check the coil and wire, maybe buy a new coil wire since you said that you are using a plug wire. Also replace the coil, I paid $15 at Advance for a replacement. I would go with the Delco though, I seem to lose spark in the higher rpms.

 

I put in an MSD coil today, took it for a ride, and so far it seems like it fixed it. I went WOT about 5 times, and it pulled all the way to 6600 w/o a problem, hopefully it stays like this Thanks for the help fellas