Gtorider510

The cel stayed off for 3 days about 100 miles of driving i guess that treatment was a waste.02 sensers would case cylinder 6 to missfire that bad?i had all my injectors checked there good and a compression test to also good. I getting sick of this crap my mpg is **** to about 17 mpg

Gtorider510

Also now when the cel comes on it only blinks for 10 seconds and goes away

svede1212

iTrader: (3)

A recording scanner with wideband O2 readings would reveal a lot.

Lovetoweld

Hi there I have 2 GTOs an 04 and an 05 Had a similar Problem with 04 ends up that it was the fuel evaporator Purge Valve I also had a hard time putting fuel in it the Valve is located up in the quarter panel by the fuel door you have to pull the plastic inner fender to find an easy easy fix and cheap there have been problems with the factory valves there seems to be out there anywhere from $15 to $40 for the money and as esy as it it to replace I would give it a shot

vroom_vroom

iTrader: (5)

Man this was hard to read. Stop putting so much faith in shops that have waisted your money. It's not running lean on both sides so that should point to something that only controls that bank. If it's only one bank it's a much narrower band of problems. My money is on bad wiring on the coil pack harness or bad wiring/ burnt up front o2 sensor. Can't fathom how anything that would effect the motor entirely would be an issue since it's only one side.

You said all the plugs where showing lean indications on that side then it's most likely a greater issue than one cyl.One cyl could be the worst of it and that's the one tripping the code.

Gtorider510

The computer has narrowed it down to cylinder 6 now.The only thing ive wasted money on was full diagnostic at this other shop it was 120 and he was working on the car for 2 whole days until he called me and said 2500 to fix i got my car out of there asap because i knew that was bs. I checked all that stuff even in the dark like someone on here said to do and i saw no arking from the coil packs r the wiring harness. He said he used a special machine to check my valves and cylinder 6 had 54 misfires. Anyway after the treatment I noticed that when its running bad it doesn't idle as rough anymore maybe it helped??? Apparently I have bad carbon build up because the ******* i purchased the car from used shitty safway gas and didnt change the oil enough and he put 80,000 miles on it like this. If it was somthing small like o2 sensers r the wiring on the coils why would it say cylinder 6 on the scanner and not all of them? Anyway if it comes down to it my freinds shop will do it for half the price of the other shop (about 1100 to 1300) im gunna have to start savin up though im pretty much fucked for now.

Gtorider510

If its multiple cylinders i guess they will have to replace those valves to he said 1100 to 1300 depending on how many need to b replaced.They send it to a machine shop to have the head ported and polished and deal with any bad valves. I was thinking since its going to be apart shouldn't i just replace all the valves instead of putting it back together with new and old valves mixed up in a brand new head?

Buzzmanb12

iTrader: (11)

Try swapping a coil pack from one of the other cylinders to see if the misfire follows the coil on #6 now, or even a whole bank of coil packs, swap left/right and see if the misfire goes to the other bank, it's easier to swap all 4 since they are mounted in a bracket. If that doesn't move the misfire then I think it is probably more of an issue with a bent pushrod, bad valve spring or bad lifter. I just don't see a valve sticking unless it has a bent stem. Pull the valve cover and look around #6, it will only cost you some time to do it.

Buzzmanb12

iTrader: (11)

You can also find some pretty good used aftermarket heads or some ported stock heads for much less than the repair of those and have a shop install them for you if it turns out to be damaged.

Gtorider510

So i will be able to see if the valve is bent just from removing the valve cover? Ok sounds like this is gunna be my Saturday project thanks for the advice!

Gtorider510

If it was a bent valve lifter r a pushrod wouldnt it run bad 24/7 and not b a on n off thing?its been running hella smooth 4 days now getting about 22 mpg and cel turned itself off i didnt use my boys scanner.

Buzzmanb12

iTrader: (11)

You wouldn't be able to see a bent valve unless it was really bent enough to hang up in the guide or was off center when seated, and the push rod would be bad all the time.
A clogged or bad lifter would/could be intermittent and could also clear itself up.

Fingers crossed that it stays running good for you.

blackbyrd

iTrader: (14)

id swap the coil packs over and see if the issue switchs banks