My idle (in park) is now around 1200 and Ive noticed my rpm's are high while driving around (3500 at 40 mph) in drive (not OD)...
--Ive done a search and see possible culprits are IAC (can you check that or just replace it? Would this affect my high rpm's while driving around?)...
--TPS (how do you check voltage and/or adjust voltage? Ive read its supposed to be .5 to .7 volts.
--If its a vacuum leak (I assume intake), how do you track that down?

 

TPS rotates after you loosen the retaining bolts. They are normally rated at 2 voltages one for closed (idle) and another at open (WOT). It's covered on the Tech Section of the main site.

Intake leaks can be a pain to track down. Some starting fluid or even a small unlit propane torch can be used find them. You're basically listening for the motor to rev up from it's normal idle when you spray around the intake. If if revs up then it's pull the flumes into the intake path.

 

Thanks..What about the IAC? Is there a way to check that or do you just replace?

Considering my RPM's have gone up across the spectrum (from idle to driving around) what could be cause that other than a vacuum leak? Ill buy some starting fluid today and see if that helps identify the issue.

 

The system can take care of a small leak but with that high an idle I'd think you could hear the leak, if there is one. Really need to come up with a scanner an look for coolant temp, intake air temp, idle air control steps, etc., to narrow down the problem. Might first check the throttle body and make sure the throttle is actually going closed, not being held open a bit by something.

 

You know its funny...My IROC is not a daily driver, I took it out today and its idling at 800 rpm in drive. slightly high but not bad.