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ike84 · 06-15-2022, 08:49 PM

305 is for cylinder 5, middle cylinder on driver's side bank.

Check all the wiring up to the coil pack for that cylinder (all the way back to the dme).

Truthfully though, if it's only happening at idle, its probably not the wiring or plug. I suspect an injector issue. Run a can of seafoam or techron and see if that helps (the more concentrated the better). Even better would be to pull that injector and bench test it.

Vacuum leaks can also cause misfire, and small leaks cause the most issues at idle, but it would be pretty unusual for it to be confined to only that cylinder. Might not be a bad idea to do a vacuum test though just to be sure.

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06-15-2022, 08:49 PM	#5
ike84 Registered User Join Date: Oct 2020 Location: KY Posts: 1,216	305 is for cylinder 5, middle cylinder on driver's side bank. Check all the wiring up to the coil pack for that cylinder (all the way back to the dme). Truthfully though, if it's only happening at idle, its probably not the wiring or plug. I suspect an injector issue. Run a can of seafoam or techron and see if that helps (the more concentrated the better). Even better would be to pull that injector and bench test it. Vacuum leaks can also cause misfire, and small leaks cause the most issues at idle, but it would be pretty unusual for it to be confined to only that cylinder. Might not be a bad idea to do a vacuum test though just to be sure. Sent from my SM-G970U1 using Tapatalk __________________ 2000 Box Base, Renegade Stage 1 performance mods complete, more to come When the owners manual says that the laws of physics can't be broken by this car, I took it as a challenge...