03 Yukon 5.3 (l59) low idle

ryanmesa · October 19, 2014

My 5.3 idled between 400-500 rpm before I cleaned TB (thought that might be the issue) and now the engine is consistently idling at 500 now. I cleaned the maf a month ago and it had a fresh air filter. It doesn't run rough and has not thrown any codes. Is the idle still too low? And is there something else that needs to be done after cleaning the TB to get it back to the correct idle speed?

02suburbanZ71 · October 19, 2014

Did you unplug battery? You should. Bad iac possibly. See dealership

00Silverado4x4 · October 20, 2014

Once my engine has warmed up it has always idled at 500 rpm. So I say your idle is just fine where it is. Now if it drops down below 500 then I would worry.

ryanmesa · November 8, 2014

It does occasionally drop below that and I'll try the battery idea but I don't have a mechanical throttle body. I have the fly by wire throttle body and as far as i'm aware they don't have idle air control valves