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Discussion Starter #1
Okay, so I have changed the plug, changed the coil pack, and changed the injector. WHAT WOULD BE CAUSING THIS MISFIRE?? Its a perfect car other than that, but im ready to let it sit in a junkyard. Please help, this is really frustrating
 

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Is it a constant or fleeting misfire? Is it throwing any other codes or is this the only one?

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You covered 3 important bases, What about fire?

If your getting fire then you could have a valve sealing issue or ring issue. Wouldn't hurt to just go ahead and do a leakdown test and compression test..
 

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I would inspect the wires to the coil and to the injector. Make sure they aren't grounding out. Also make sure the connectors are okay and there isn't any bent pins.
 

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Discussion Starter #6
Alright thanks everyone for replying. I haven't done a leak down or compression test because honestly I don't know how to... But.i did find out that the cylinder 1 Coil had a loose wire, and the lock tab was broke. You could hold down on it and hear it sound different. I replaced it, but it seems like once i fixed that, i get cylinder 4 misfire and cataylict deficiency on both banks
 

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6 Cylinduh, Really Bruh?
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Alright thanks everyone for replying. I haven't done a leak down or compression test because honestly I don't know how to... But.i did find out that the cylinder 1 Coil had a loose wire, and the lock tab was broke. You could hold down on it and hear it sound different. I replaced it, but it seems like once i fixed that, i get cylinder 4 misfire and cataylict deficiency on both banks
I had a stupid tab break on me on a fuel injector. Small zip tie fixed it.

What codes exactly are you getting?
 

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Slo_n_low
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You could swap the coil pack with one from another cylinder and see if it leads to a misfire in that cylinder instead. That would confirm if the COP is good or bad. Not sure if you can do the same with injectors since I've never pulled one. But if ignition and fuel is good, then time for a compression check. If one cylinder is a bit low, put about a tablesoon of oil in and see if it raises it. If so, then bad news time for a rebuild or new engine. If it has like no compression or crazy low, then most likely an open valve which requires a head job.
 

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Discussion Starter #9
You could swap the coil pack with one from another cylinder and see if it leads to a misfire in that cylinder instead. That would confirm if the COP is good or bad. Not sure if you can do the same with injectors since I've never pulled one. But if ignition and fuel is good, then time for a compression check. If one cylinder is a bit low, put about a tablesoon of oil in and see if it raises it. If so, then bad news time for a rebuild or new engine. If it has like no compression or crazy low, then most likely an open valve which requires a head job.
Done all that. The compression test all of then came ouy between 170-180
 
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