"Misfiring" Somebody help...please!!

[Pewter99Camaro]

I replaced my plugs the other day. Put in 6 Champion Platinum plugs and a set of Accel Wires. After driving for about 10 to 15 minutes, when I floor it, sometimes it shutters like it is misfiring, but it doesn't do it all of the time. What is my car doing? Could it be that the wires are maybe wrapped around each other and the sparks are interfering with each other? Or, could it have something to do with hollowing out my cat? Please email me or post a reply because I am in the dark with this one.

[kahouna23]

Knocking the internals out of your cat wouldn't do that unless you have 3" straight exhaust out the back. Backpressure really isn't that necessary and what little is needed for the engine is a very small amount. You could hold your hand 6" away from the exhaust tips and that would be sufficient backpressure. As for the stuttering, I would say you could possibly have a faulty wire, or the boots aren't installed correctly, making a good connection. Check all your connections. One could have been on just enough and when you started driving, the vibration knocked it loose causing a "misfire" under acceleration. I had a very similar case a while back and that was the cause. If all your wires turn out to be good and the connections are fine, check the plugs to see which one is faulty. If it is an ignition problem to begin with. Could be something fuel related. Doubtful, but possible. My guess is the connections on the plugs or coil. Another small tip for ya....put just a dab of vaseline on the inside rim of the boot. This makes it easier to pull them off without hurting the wires.

[Tireguy]

I had some work done on my maro. in the shop a couple months ago, new E.G.R. Anyways, it started backfireing at high speed. Turns out they ran a plug wire against something hot and it chaffed threw. I pulled it in my garage with the lights off and opened the hood. Saw sparks comeing from the cut wire after it warmed up. Give that a shot. I replaced the wire and just moved it. Good luck. [img]graemlins/thumbsup.gif[/img]

[Pewter99Camaro]

I'll try that. Thanks for all of the help!

[SecretAgent420]

did you gap your spark plugs right your put them in right?

[RSFireDog]

I'm goin with the rest of 'em, I bet you didn't put something back in right.. probably just a loose connection..

[O2Bsogood]

I know this would suck to do. If there are no wires touching anything hot or anything at all wrong with the wires. I'd take each plug out and look at them. You might have accidently pushed the electrode into the tip, if they aren't gapped apart it'll make you stutter when you get on it. It'll idle fine and run at lower speeds without much differnce but when you go to get on it it'll let you know.

[Shay]

You know, I just had this problem and did everything like plugs and coils.....except the wires. I got under the car at night with the engine running and turn my drop light off. I saw my wires closest to heat sheilds or whatever metal would arc through the insulation. Granted my wires old OEM that needed to be replaced. That being done, no more misfires or shuddering when I hammer it. With my wire it was age that was the problem. If your Accels are new or fairly new I doubt you insulation has broken down. Did you use the universal 8.8 Accel wires. If so might be one of your connections where a boot is, acring to the engine block or something metal or maybe like someone mentioned might of hit something hot and melted the insulation exposing the conductor. Anyways hope this helps.
P.S. If you decide to get under the car like I did be safe and smart about it.