LOL, when it rains it pours.....I recently had to install a new water pump on my LS1, and everything went easy as pie, but since I had to remove the throttle body for easier access to the pump, I went ahead and cleaned it with a little bit of throttlebody/carb cleaner taking extra steps not to soak (or even directly spray) the IAC (idle air control). So upon driving it around to make sure there were no leaks, the engine would idle around 1100 RPM, sometimes 1000, and the only time the idle would be normal is at startup. So....I can't possibly think why this is happening. please help!

 

are you throwing any codes. If not try to see if you got your IAC wet or have any cleaner left over in your TB Try to let it dry or drive it for a while and see if either the problem clears it self up or if your ecu catches a code.

 

Did you get the bellows on all the way around the TB? Sometimes it doesn't go on the bottom causing an unmetered air leak.

 

Yeeeup, that bellows is on that throttle body tighter than a gold digger on Bill Gates... But really, This prob is seriously irritating. I'm pretty meticulous with my LS1's care... Anymore ideas please??!!

 

i would make this priority (that is if you know that there are no problems with the TB or bellows or likage). sometimes it takes several miles of driving or having it run for a while before it will pop up on the dash (CHECK ENGINE). the ECU may also try to compensate for the mistake ( to a certain point)

if you cant find any mechanical problems the check for codes.

 

The IAC should reset itself during highway driving. If it is damaged though, the computer is trying to do something the coils in the valve aren't going to do. Unfortunately, the replacement cost is around $100 for the stupid thing so you can't just throw a new one on. I would take it off the TB, make sure there is not carbon on the pintle, and then carefully push it all the back. This should allow the computer to get a "fresh" view of the valve and then reset it during highway driving, usually around 30 to 40 mph.

 

OK here's another idea. Do a PCM reboot and idle learn.

 

Thank you everyone for your input!
I am going to take your ideas and run with them tonight.... I did my daily driving routine today and the idle was still higher than normal. I remember that when I cleaned the TB, I only cleaned around the IAC, so no direct spraying, soaking, being rough with the pintle, etc. So, no codes popping up, either... So, tonight, we'll see! Thanks guys