Did you monitor the fuel trim on a drive. I found that my FT was also high (16) after a long idle time, but went back down while and after I took it for a short drive.

 

it should be 0 if everything is right...even after running for a while.

 

Then maybe I need to look for a problem in my MC. Lol. Thought she was running pretty good.

 

hey guys sorry to jump in, I have the same code
did the spray carb cleaner trick to find a leak
seemed like it was where throttle body met intake but on close inspection today I found an intake hole that seems to feed the iac motor

you can feel the air sucked in during idle, is this normal?

 

Hey bossross, no apology necessary. Could you describe the location of this hole a little more precisely. I don't have any codes, but this could explain the 16% LTFT after long idle. You're talking about the UIM right?

 

20-25% will throw a code...10% ltft is fine,i was told 16 is to high,I should have MAF today..using a non GM one i was told it can be skewed,not reading correctly..hopefully this new gm one will help with my problem.

 

yes the uim. directly to the left of the iac

 

I did carb clean too but i didnt see that leak on the pcv cover.. Smoke found it.

 

MAF is in,will put it in after work,cross fingers and we will see if it does anything...

 

STFT 0% LTFT 0% ...maybe I have to take a ride but,right off the bat it read normal...so was the Cardone MAF just screwed up and sending more fuel to the car or ws it just reading wrong to the scanner?