Scanned - not a misfire, need help.
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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
you may also have a bad plug wire. it will not arc out, it will fail under heavy load though. pull the wires and do a resistance check. the readings should all be very close to each other (ohms)
Thread Starter
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Hi
Did a little more investigation, it is not a leak but definately a misfire at WOT. No exhaust leaks.
Plugs were out when the swap was done. They were inspected and in good shape. The shop told me they were carefull with them.
I think I will take it back to the shop and ask them to swap out the MSD wires for the old GM ones. If that does not fix it, I assume I am screwed. Without it showing up on a scan it will be hard to fix.
Thanks JA
Did a little more investigation, it is not a leak but definately a misfire at WOT. No exhaust leaks.
Plugs were out when the swap was done. They were inspected and in good shape. The shop told me they were carefull with them.
I think I will take it back to the shop and ask them to swap out the MSD wires for the old GM ones. If that does not fix it, I assume I am screwed. Without it showing up on a scan it will be hard to fix.
Thanks JA
