Help--P0307
Thread Starter
Pro
Joined: Aug 2003
Posts: 574
Likes: 110
From: Louisville
Help--P0307
So I finally got my car back after the builder/tuner blew up #7 some months ago. I have it back now and after about 500 miles I'm getting the P0307. This started after installing one of the numerous tune changes the builder has sent me to clear up a transmission issues...now this. My 03 has a forged bottom end, mild BTR SC cam, long tube headers, built transmission, A&A SC w/3.6 pulley, Deko 80lb injectors, and A&A fuel system.
I changed the #7 coil but I'm still getting the code. I didn't think it was the coil after 500 miles but wanted to check. With this being such a fresh build is it possible that something is wrong internally? I added my current tune in case i'm just missing something in the tune. Thanks
I changed the #7 coil but I'm still getting the code. I didn't think it was the coil after 500 miles but wanted to check. With this being such a fresh build is it possible that something is wrong internally? I added my current tune in case i'm just missing something in the tune. Thanks
Pro
Joined: Oct 2020
Posts: 529
Likes: 197
From: Columbus, MS
Usual isolation routine-- change the following parts from cylinder 7 and a known-good cylinder
1. Coil (sounds like you did that already)
2. Wire
3. Spark plug (take a look at it when you remove it, look for anything unusual)
4. Fuel injector
Swap these parts one at a time and see if the miss moves to a different cylinder. If it moves you know that the last part you moved was the culprit and you can replace it and hopefully be good to go. If none of those parts move the miss you can do a compression test to see what you get for that cylinder. You can also horoscope that cylinder by sticking an inspection camera down the spark plug hole and look for anything unusual about the piston head and cylinder wall.
1. Coil (sounds like you did that already)
2. Wire
3. Spark plug (take a look at it when you remove it, look for anything unusual)
4. Fuel injector
Swap these parts one at a time and see if the miss moves to a different cylinder. If it moves you know that the last part you moved was the culprit and you can replace it and hopefully be good to go. If none of those parts move the miss you can do a compression test to see what you get for that cylinder. You can also horoscope that cylinder by sticking an inspection camera down the spark plug hole and look for anything unusual about the piston head and cylinder wall.
Drifting
Joined: Apr 2007
Posts: 1,517
Likes: 159
From: Lafayette Louisiana
Plug looks wet. I would start off with new plug and swap wires with another cylinder. If problem does not move then swap coils with another cylinder. Hopefully one of those will be the problem.
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