Oil Leak - Blue Smoke

[Trumpet Man]

Hello, I owned a 2007 Yukon SLT with high mileage.  Lately experiencing rough start up with blue smoke.  As the SUV warms up, there is less or no blue smoke.  It is believed worn valve seals or a valve cover with bad internal PCV, but unsure.  Therefore, I am seeking advice to fix the problem. 

 

Thank you

[CamGTP]

Pull your spark plugs and see how bad they look. Cylinder 1, 4, 6, 7 are AFM/DoD cylinders and those are worst for oil build up. If they are covered in soot/oil that would be the cause for the rough start up.

 

There is a revised drivers side valve cover that does fix the PCV issues on the early model year trucks, it may or may not help at this point.

 

It's possible it's valve seal related or the bigger issue is that the oil is getting past the piston rings and causing the engine to burn oil. The piston ring issue tends to be more common on early high mileage AFM engines.

 

 

To really fix all the problems instead of just slowing down what is already happening, you would need to rebuild the engine. Hone the cylinders, new pistons/rings, new lifters, new VLOM plate and all that stuff.

Edited September 23, 2020 by CamGTP