Thread: k i got a cylinder 4 miss and im running out of options

Originally Posted by DaytonaGTP

i just kinda gave up on mine. it doesnt throw a code anymore. its almost not noticable and sometimes it doesnt happen at all. the only thing i can think of that i did was do something to the rear head when i had straight pipes. but yeah in case you are all wondering i never fixed it i just let it go... doesnt really bother me. 230k miles so i figured its a normal thing now

Mine is high mileage, too. 180k. As I said earlier, it seems to clear up to an acceptable level as the operating temp rises, which got me thinking about it being a "cold" plug and maybe I would bump the heat range on #4 up a little. Hard to figure an engine that operates "normally" close to 210F could have a cold cylinder though.

BUT... I have also recently noticed the miss comes back if I shut down and re-start...like on a trip to the store. That kinda tells me the problem might reside in the closed loop "warm up" cycle of the computer. So now I'm wondering if at some point these high mileage cars might need to be re-flashed. Anybody tried that? ~FH

Originally Posted by 01gpgt01

I wouldnt go mix matching heat range on plugs. These cars are notorius when moded at having mis and surging during closed loop operation. Some people have had luck with tuning.

No mods on this engine... that I know of. Just came out of a plug/wire/oil change. Just for giggles & grins I'll have the 'puter reflashed and see what happens.

As widespread as this #4 misfire seems to be on the 3.8 it's surprising no tech bulletins or fixes have been found by now. I do a lot of multiple stop daily driving and if it weren't for the closed loop miss on restarts I guess I could live with this particular gremlin. But just knowing the engine is out of balance for a few minutes and remains an unresolved problem bugs the crap out of me. ~FH