Still have a misfire
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Still have a misfire Hi all, I have a 2000 ls1, check engine light is on coming up as cylinder 2 misfire, changed injector, coil pack, plug, wire, compression test, checked for vacuum leaks, pulled valve cover off and everything looks fine, I'm out of ideas as to why it would still misfire, any help is greatly appreciated!
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Teching In
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Thread Starter
Teching In
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Thread Starter
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But no check engine light code for an o2 sensor? Only code that comes up is p0302, definitely starting to be a mystery since everything is changed on that cylinder
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Originally Posted by diver2522
Ill try a leakdown test next I suppose, changed both upstream 02's today and still misfiring ugh
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By the time I find the misfire I'm hoping it is something dumb lol, I'm going to try to do the leakdown test this weekend, just boggles my mind with everything that I've changed on that cylinder and it still misses on that cylinder, if the leakdown test goes good, then I'm totally lost lol
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If this problem is intermittent like you are saying then it couldn't be leak by right? like that would be constant I think it has to do with fuel if you checked your injectors, plugs and coils then I would check the O2's. Even if they are brand new sensors I've had them go bad. Does the car idle on cold start fine? and when it warms up starts to miss? That would also point to O2 sensors. Other thing would be to check wire harness that goes to #2 and see if it got wet or some kind of damage to it? Just throwing out ideas. Hopefully you didn't reverse the harness or something weird??
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I never removed it, not sure if the previous owner ever removed it, would you maybe recommend spraying some throttle body cleaner around the gasket area? I've done it before and heard no change in the idle at all but can try it again
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There are eight separate intake manifold gaskets on the LS1, so it's possible just one could go bad.
Since #2 cylinder is on a corner, the intake manifold bolts may need to be retorqued.
Edit: Just to clarify, I'm not referring to the throttle body gasket. The intake manifold gaskets seal
the intake manifold to the ports on the cylinder heads. There are ten bolts attaching the intake manifold
to the engine.
Since #2 cylinder is on a corner, the intake manifold bolts may need to be retorqued.
Edit: Just to clarify, I'm not referring to the throttle body gasket. The intake manifold gaskets seal
the intake manifold to the ports on the cylinder heads. There are ten bolts attaching the intake manifold
to the engine.
Last edited by 88bruce; Feb 25, 2020 at 12:55 PM.