GMC YUKON HYBRID P-0300 code

[53' Stude]

So, this morning brother says the 09' Yukon Hybrid was flashing the check engine light on way home last night. He has new plugs, and we pulled intake manifold that was full of oil. He's going to order the "revised LS valve covers" for it. Plugs to my eyes looked downright nasty too. 135k on vehicle. Anything else he should look out for? Thank You

 

[14Accent]

I can almost guarantee it's got carbon buildup in at least the #7 cylinder. P0300 doesn't give enough info, you need to look at the misfire history data on a full scan tool and see which cylinder's are the one's misfiring.

 

[53' Stude]

Originally Posted by 14Accent
I can almost guarantee it's got carbon buildup in at least the #7 cylinder. P0300 doesn't give enough info, you need to look at the misfire history data on a full scan tool and see which cylinder's are the one's misfiring.



Thank You for the info. I'll keep this post updated

 

[97prizm]

Not sure of the years but it sounds like there is a TSB for the Yukon Tahoe hybrids.

From the Repair order: 93391 P0300 eng miss fire detected. found sparkplug cyl1 oil fouled. replaced Valve Rocker Arm Cover and spark plug. J7576 1.2 per bulletin 12-06-01-001B
Parts and Labor 237.46 (warranty item)

 

[53' Stude]

Thanks for the heads up, I'll pass it onto him ðŸ‘