96SilverZ

iTrader: (2)

Since my header swap I've been trying to fix this multiple cylinder missfire code before I have to go back to school so all help is appreciated

Along with this code I have two others for the rear o2s and I still need to plug a hole or two in the egr/air system. During the swap I was careful to make sure the plug wires were tucked away but I've already replaced one and I've noticed that oil is leaking around the opti.

The missfire is only at low rpm's under load and clears up at 2500+. Also, is it possible that false knock from the headers is causing this?

96TransAmboosted

iTrader: (8)

Maybe you broke a plug when installing the headers? Did it do it before the swap? Maybe a wire is arching on the header or block?

96SilverZ

iTrader: (2)

It started after the header swap. I'm sure I didn't break a plug because I removed them for the swap. I'll go check to see if anything is arching but I doubt it.

96LT1355Z28

iTrader: (2)

Does it feel like its misfiring or just setting the code? If you have an exhaust leak and just did headers fix the leak and check your O2's. Leaks can cause the O2's to sense too much air affecting the fuel trims. It's been reported by some that their O2's had issues after installing headers due to the burning of paint, rust inhibitor, etc. inside the new exhaust.

96SilverZ

iTrader: (2)

When it's missing you can tell it shakes the car and falls flat on it's face. I knew about the headers damaging the o2's but the code came up right after I finished the swap so unless they get damaged that fast I'll wait on replacing them. I had no clue an exhaust leak could change the o2 readings so I'll get that fixed.

96TransAmboosted

iTrader: (8)

If the o2 sences leaking air that would cause your fuel trims to change resulting in missing and poor performance. Or you could still have a cracked plug or loose wire.

96SilverZ

iTrader: (2)

problem turned out to be the ignition coil. I could see it arcing at night. Hopefully this helps someone else out.