The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 07 avalanche p0302 code driving me nuts...

heartattack · 12-13-2021, 02:57 PM

You can squirt a small amount of oil in #2 cylinder with the spark plug removed. Spin the engine over and see if your compression shows a increase. if it does, then its most likely ring related.

I would guess its carboned rings. If so, buy the GM top end cleaner, pour some in each cylinder and let sit overnight. spin the engine over the next day with the spark plugs out to clear the fluid. Install the spark plugs and go drive the truck to clear out the residue.

12-13-2021, 02:57 PM	#7
heartattack Registered User Join Date: May 2013 Location: Ms Posts: 19	Re: 07 avalanche p0302 code driving me nuts... You can squirt a small amount of oil in #2 cylinder with the spark plug removed. Spin the engine over and see if your compression shows a increase. if it does, then its most likely ring related. I would guess its carboned rings. If so, buy the GM top end cleaner, pour some in each cylinder and let sit overnight. spin the engine over the next day with the spark plugs out to clear the fluid. Install the spark plugs and go drive the truck to clear out the residue.