Has to have been a screwed up Cardone MAF 'cause the scanner is reading what info. the PCM see's. The PCM does what the MAF tells it to do. DO you think the PCV cover or the MAF was the culprit? I know it's been a long battle for you, but it really sounds like a success story. You must really feel some satisfaction in the results. I'll keep fingers crossed for you that it stays that way, but I feel pretty confident that it will. Glad I could help with this, it's been fun. I think I learned as much as you and now think maybe I need to change my MAF to get to 0% as well. Keep me posted.

 

bossross, I haven't had a chance to look into the hole in the UIM, but I think your logic sounds right and it's normal. It's likely a breather hole for the IAC motor. It probably balances the "Pintle" during idle. if your problem sounds similar to avendo's I would read through this thread thoroughly and follow the lessons and techniques in troubleshooting. The smoke test for vacuum leak(s) and replacing the MAF with a genuine OEM GM one seems to have been the key.

 

I would not have believed it if I did not see it I want up-and-down that Car looking for a vacuum leak according to what the computer said now I have to try and take the cardone one back to AutoZone they don't warrantee except for giving you a new one watching that video on fuel trims is a big help too i'm glad I taught some other people things I grew up as a MacGyver fixing stuff and troubleshooting stuff all my life

 

well the p0420 code came back on today,booo.

 

Darn, just when you think your done.......

 

got to check wave forms today on scanner.

 

Keep me posted. Changed the MAF and PCV valve kit on mine after your experience and now at 0% STFT and 3% LTFT.

 

See i started something lol

 

Will a bad cat screw up my gas milege? Should i get a high flow cat?

 

bought cat from rockauto 166.00 hurts to do but..