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Apex24
10-10-2016, 02:37 PM
I've been trouble shooting this problem all year long and I'm at a dead end.

The issue started out as a bad misfire in cyl 2. I could turn off car, wait 30 sec, restart and misfire would go away until the engine was under a load again and then it would come back and stay until I turned the car off. Code was for Injector failure cyl 2 so I replaced injectors with some reman injectors. Same issue, same symptoms remained.

Replaced injectors with new injectors. Same issue, same symptoms remained. Still code for injector fail cyl 2.

Replaced coil pack on cyl 2, inspected all other coil packs and boots and everything looks fine. Cleaned all the contacts to ensure they're making good connection. Inspected the harness for any defects, everything looks fine.

Now the misfire is not as harsh after swapping the coil pack out and it comes and goes. It will misfire with anything above 30-40% throttle but if I let it come back to idle sometimes it will clear itself up, other times I have to restart the car to get it to go away. Now, I'm not getting any codes for the misfire or injector. Only code I've got is P0601 int memory check sum err (this code has always been there since I had car tuned)

At this point I'm at a loss as to where to look. Plugs all look fine and I replaced them when I was foolin around with the injectors. From my research on the forums some people say cam position sensor? I'm looking for some advice as to where to go from here.

Apex24
10-24-2016, 10:16 PM
Replaced the camshaft position sensor, while I'm sure it was worth it, it didn't solve my immediate problem.

I spent the whole day Saturday going back over everything I had checked/replaced up to this point. It turns out one of the new injectors was bad, swapped in another injector and boom, good as new.

So my advice to anyone who is chasing a phantom issue is to check, recheck, and triple check everything. Also, don't take anyone's word that a part is 'good' even if it's new, test it and check it yourself to make sure it's working properly.