The issue started with a leaking valve cover gasket. Replaced gasket, pcv valve, and adjusted valves. Exhaust valves were all too tight.

After that, car threw CEL P0507 and P0171. Took the throttle body out and cleaned it with throttle body cleaner. Used Autel MK808 to do throttle body position test, reset the throttle body, and reset ECM.

Did throttle relearn procedure, CEL comes back. Tried driving for about a hundred miles, figured there was a vacuum leak. Did smoke test from the intake tube, intake tube was leaking where it attaches to the throttle body. Couldn't get it to seal. Got new intake tube, redid the smoke test, no smoke anywhere.

Car idles steady anywhere from 1500 to 2000 rpm. Tried unplugging MAF, no change. I pinch the PCV hose and the idle drops to about 800.

Car is still acting like theres a vacuum leak. Any ideas?


Thanks,

Joe

 

Figured it out. Apparently, the replacement valve cover from Amazon is defective. Dozens of people complaining of a defect in the molding of the PCV housing that causes P0507 in the reviews. Ordered a used OEM valve cover off of Ebay.

 

I would not have guessed that one. Thanks for posting up the solution to the problem once you found it. So many never post back up.