Scanned - Not a misfire, need help
06-10-2006, 12:03 AM
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Scanned - Not a misfire, need help Hi
Re 98 Camaro Z28, A4
Makes a loud popping sound from the exhaust only under WOT. Engine runs rough when it happes. Under partial throttle it is ok. Thought at first it was a misfire, but the scan was negative. I checked the exhaust and it is tight. I cannot find any leaks at the manifolds, cats or Y pipe. Also, no physical contact.
Should I be looking at AIR or EGR gaskets. Any help is appreciated.
Thanks JA
Re 98 Camaro Z28, A4
Makes a loud popping sound from the exhaust only under WOT. Engine runs rough when it happes. Under partial throttle it is ok. Thought at first it was a misfire, but the scan was negative. I checked the exhaust and it is tight. I cannot find any leaks at the manifolds, cats or Y pipe. Also, no physical contact.
Should I be looking at AIR or EGR gaskets. Any help is appreciated.
Thanks JA
06-10-2006, 01:35 AM
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any mods? Almost sounds like you're running rich and back firing.
Or maybe predetonation.... what grade fuel do you use?
Has it always done this or just started out of the blue... or after you did something.
Or maybe predetonation.... what grade fuel do you use?
Has it always done this or just started out of the blue... or after you did something.
06-10-2006, 11:39 AM
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How long have you been running it like this? Maybe a code just hasn't been thrown yet. Do a search for "drive cycle" there is a writeup that tells how to have the take your car out and have the computer do a complete scan. That will show any codes that haven't popped up yet.
06-10-2006, 09:04 PM
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Hi
Did a little more investigation. It is not a leak in the exhaust but definately a misfire. Only at WOT. Partial throttle is OK. I use 94 octain.
There is some history. Just had the stock exhaust swapped back in after taking headers out. The plugs were inspected at the time and they were in good shape. I am hopping it is just wires. They all apear to be on tight.
Only mods now are K&N induction, Borla cat back and MSD wires. I thinking I should swap the old wires back in now. Any sugestions?
Thanks JA
Did a little more investigation. It is not a leak in the exhaust but definately a misfire. Only at WOT. Partial throttle is OK. I use 94 octain.
There is some history. Just had the stock exhaust swapped back in after taking headers out. The plugs were inspected at the time and they were in good shape. I am hopping it is just wires. They all apear to be on tight.
Only mods now are K&N induction, Borla cat back and MSD wires. I thinking I should swap the old wires back in now. Any sugestions?
Thanks JA