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hunting down p0301 cause ...

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Old Feb 9, 2018 | 03:08 PM
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Default hunting down p0301 cause ...

02' auto, stock not even a lid. true duals after the cats that's all.
... ok so no probs with the car at all running fine UNTIL i do a plug & wire change. i then get p0301. have cleared it multiple times it's the only code that comes back. ok so i changed out ALL the new spark plugs & wires with MORE NEW spark plugs & wires, & bought/installed a new coil pack for cylinder 1 to no avail - same code/results ___ swapped out 3 different plugs & wires with both the new and old coil pack installed on cylinder 1 with SAME results/p0301.
Acts exactly as a misfiring car would, bad rough idle that gets worse/loses more power in either drive or reverse/car shakes enough for you to know it's misfiring. i have also cleaned the maf & tb off car very well with maf & tb specific cleaners.
.... ok so a friend suggested bad injector, but remember this has only happened seemingly due to the spark plug & wire change. ANY input/ideas ?
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Old Feb 9, 2018 | 04:34 PM
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You can try moving the coil pack on the bad cylinder to see if the fault follows. If it's firing at all, it's probably not an injector, though I wouldn't rule that out completely.
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Old Feb 9, 2018 | 04:37 PM
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I agree, swap the coil packs from bank to bank, see if the code changes. Possibly damaged wiring to the coil.
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Old Feb 9, 2018 | 05:02 PM
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If you still have issues after swapping, bust out the multimeter and start checking the pink wires for 12 volts at the coil. It won't always be exactly 12, but if you do have a damaged wire, it will be well under that. I want to say mine read somewhere around 11.8 with the engine off.

Check your grounds too, especially the ones on the backside of the d/s head.
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Old Feb 9, 2018 | 05:05 PM
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Originally Posted by ss.slp.ls1
I agree, swap the coil packs from bank to bank, see if the code changes. Possibly damaged wiring to the coil.
And yes, I meant to say the bank. It's super easy to pull off and swap to the other side. Just make sure you flip them so the reference wire colors are still in the right spots. The #1 and #8 cylinder reference wires are the same color. I want to say it's purple, but it's been a while.
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Old Feb 9, 2018 | 07:37 PM
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yea not an injector i just swapped 2 injectors & same thing. ok so even though i put a new coil pack in cylinder 1's place, i'm gonna swap it with another & see what happens
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Old Feb 9, 2018 | 07:46 PM
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Originally Posted by SkWiDsTyLe321
yea not an injector i just swapped 2 injectors & same thing. ok so even though i put a new coil pack in cylinder 1's place, i'm gonna swap it with another & see what happens
Swap the whole bracket to the other side. This will rule out or confirm if your have a bad harness on that bank.
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Old Feb 9, 2018 | 08:33 PM
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Originally Posted by ChopperDoc
Swap the whole bracket to the other side. This will rule out or confirm if your have a bad harness on that bank.
... that's what i'll do for sure - thank you
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