P0300 after header install and PCM flash
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Joined: Feb 2010
Posts: 80
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From: Upstate NY
P0300 after header install and PCM flash
So i sent my PCM to ECS to get flashed for my header install (no cats).. Had him delete rear o2s but they are still in the plugged in, not sure if that matters.. So i fire it up, running great.. Noticed i had a leak on the driver side where the header meets the resonator (donut gasket).. Figured i would take it for a spin and then tend to the leak later.. So i get about 1/2 mile down the road and it starts to sputter real bad.. I had no power at all what so ever... CEL started to flash so i took it back home and i had P0300 on my scanner.. Pulled a few plugs out.. Drivers side was real bad all the plugs were BLACK and the passanger side was normal.. the o2s are crossed... The exhaust leak wouldn't cause a misfire would it? not sure where to go from here..
Thread Starter
Advanced
Joined: Feb 2010
Posts: 80
Likes: 0
From: Upstate NY
i changed plugs/wires a month ago.. i might have a bigger problem because the drivers side all four plugs are BLACK and the passanger is side is all normal.. Ill start the car and it will idle great then when i give it gas or try to take off it will almost die right out... could an exhaust leak cause misfires like that?
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Joined: Jan 2007
Posts: 19,482
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From: Dyer, IN
So i sent my PCM to ECS to get flashed for my header install (no cats).. Had him delete rear o2s but they are still in the plugged in, not sure if that matters.. So i fire it up, running great.. Noticed i had a leak on the driver side where the header meets the resonator (donut gasket).. Figured i would take it for a spin and then tend to the leak later.. So i get about 1/2 mile down the road and it starts to sputter real bad.. I had no power at all what so ever... CEL started to flash so i took it back home and i had P0300 on my scanner.. Pulled a few plugs out.. Drivers side was real bad all the plugs were BLACK and the passanger side was normal.. the o2s are crossed... The exhaust leak wouldn't cause a misfire would it? not sure where to go from here..
