Thread: Cylinder 3 misfire Tried everything I can think of

Safety isn't an issue, just don't run it for a long period of time because it will get MESSY!!! You're squirting oil all over and might catch fire on the headers. Slim but possible. I've adjusted rockers this way on several older V8's I've built. Just clean your header good afterwards and everything else.

Did you switch coil packs around? I know you switched wires. Don't know about the ICM. My experience is they either work or don't, but could be a short in your ICM. Would a crack between your exhaust and intake valves show up on a compression check? Crack might show up more under more heat and that being a middle cyn. it gets hotter then the outer two.

Originally Posted by dbextreme

Safety isn't an issue, just don't run it for a long period of time because it will get MESSY!!! You're squirting oil all over and might catch fire on the headers. Slim but possible. I've adjusted rockers this way on several older V8's I've built. Just clean your header good afterwards and everything else.

Did you switch coil packs around? I know you switched wires. Don't know about the ICM. My experience is they either work or don't, but could be a short in your ICM. Would a crack between your exhaust and intake valves show up on a compression check? Crack might show up more under more heat and that being a middle cyn. it gets hotter then the outer two.

yeah thats what I was told about the cylinder 3 and 5 tend to be the leanest and misfire will occur in those first or chipped pistons or commonly 3

dont think exhaust leaks would show up in compression test and yeah I had swapped coils and ICM both leaving me with the same intermittent misfire
it actually got more dominant after swapping icm and than even out after a pcm relearn all my ftlts and vac levels seem appropriate though even at high speeds not sure if the vac would be affected by the exhaust leak either

gonna check the valves tomorrow than just worried its not going to act up for me unless I throttle the hell out of it at the moment the problem only occurs on boost