2001 yukon denali 6.0 oil in cylinder 1 and 3

[tendempine]

I have a 2001 gmc yukon denali 6.0. I had taken my car to a mechanic to get a dionostic and he told me I have oil in cylinder 1 and 3. He said he cleaned out the oil and it came back when he started it. It runs with loss of power and has a random misfire code. Is there anything I can try before replacing my head gasket

 

[OR VietVet]

Welcome to the forum from Oregon.

Sorry about the problem with your truck.

Miles on the engine? Random misfire code for 1 or 2 cylinders are are/is for cylinder 1 or 3 or both? Oil in cylinder can foul the plugs. Were the same plugs reused when "cleaned out" and restarted? How was the oil cleaned out? Was a dry and wet compression test ran? If so, what were the results?

 

[tendempine]

Welcome to the forum from Oregon.

Sorry about the problem with your truck.

Miles on the engine? Random misfire code for 1 or 2 cylinders are are/is for cylinder 1 or 3 or both? Oil in cylinder can foul the plugs. Were the same plugs reused when "cleaned out" and restarted? How was the oil cleaned out? Was a dry and wet compression test ran? If so, what were the results?

The engine has 193k miles and I don't know how the oil was cleaned out and yes the same plugs where used. The code says random misfire and he told me it's for cylinder 1 and 3

 

[Marky Dissod]

Either the rings are letting oil in from the bottom,
or valve seals are letting in oil from the top.
How else would oil get inside a combustion chamber?

 

[OR VietVet]

Old plugs were likely fouled. Can cause a misfire, even if oil is not getting back in. Compression test, dry and wet, is needed.

 

[Mudsport96]

Either the rings are letting oil in from the bottom,
or valve seals are letting in oil from the top.
How else would oil get inside a combustion chamber?

Could be that the pcv system has flooded the intake manifold with oil and that is getting in the cylinders.

 

[rockola1971]

I have a 2001 gmc yukon denali 6.0. I had taken my car to a mechanic to get a dionostic and he told me I have oil in cylinder 1 and 3. He said he cleaned out the oil and it came back when he started it. It runs with loss of power and has a random misfire code. Is there anything I can try before replacing my head gasket

Head gasket replace for oil in the cylinders? Watchu talkin' about Willis????

Youve got oil running down valve stems because of bad valve seals or you have bad rings on those cylinders. A compression check across all 8 cylinders will tell you whats up with your rings. Otherwise pull your valve covers and plan on replacing the valve seals when you take them off.

 

[Marky Dissod]

I have a 2001 gmc yukon denali 6.0. I had taken my car to a mechanic to get a diagnostic and he told me I have oil in cylinder 1 and 3 ...

Could be that the pcv system has flooded the intake manifold with oil and that is getting in the cylinders.

Cylinders 1 & 3 only?
And this likely has nothing to do with a head gasket.