I have a 2010 mcs with a few modifications. Exhaust, dp, intake, sprintbooster, and wheels. The other day I lost from what I figure is around 20% power. I also started to notice a burning oil smell. It happened within a period of an hour or so. Took my son to his mother's via the interstate, and on the way back.....gone. I had my intake valves cleaned less than 5k ago, and seafoam every 3k. I've heard stories of the valve cover pcv doing this, but is it the most likely culprit? Pulled a code that said it was downstream air leak post maf. Any tips, and has anyone changed valve covers/pcv and fixed this issue?

 

Was the code p115c? Cause if it is... good luck with trying to figure out what is causing it.

 

No not the same number.

 

Well..what was the number?

 

I pulled p1497. But yours relates to the same issue. Valve cover or pcv in valve cover might be a possibility. Not sure though.

 

Think that code has something to do with a vacuum leak. So yes, the valve cover would prolly be the culprit. Are you hearing any kind of hissing after shutting the car off?

 

No hissing from what I can hear. The typical cool down cycle begins per usual, but no strange noises. I cleared the code around noon here, put 30 miles on and it has yet to show its face again.

 

It is still low on power. Would plugs make a difference like that and that quickly.?