if i can unplug my iac on my car with it idling, and it still holds the same idle with absolutely no change, would that lead one to conclude my iac is bad ? it doesnt throw any codes, or anything, and the guy i had scann it said it shows to be trying to idle itself up, but there is no fluctuation in idle.. i have looked and found that the throttle blade has been cracked open enough to make it idle like it is... so would you think my iac is bad?

 

Texas, the IAC is a stepper motor design that moves the valve in and out via a worm gear setup. When the IAC is disconnected the plunger or valve retains is physical position. The scan should indicate the IAC counter which can step the plunger to 125 positions (IAC Counter) . The normal setting with the TB stop cranked slightly open would have the IAC counter around 25-30 at idle in N. If the counter is stepping up and the idle is not changing then either its jammed or the air passage is blocked. Look at the TPS sensor voltage it s/b below .71 volts if the TB stop screw is correct. Your sig says 52mm TB so your numbers may be different for a modified TB setup.

 

ok i got yah.. i just pulled the iac out and turned the key to the on position, and the iac doesnt even move, when the key is turned on isnt it supposed to cycle in and out to some degree?? and the tps is new and was at .55 volts when we installed it and checked it ...

 

it sounds like ur iac is bad to me.

 

ok i had someone else try checking the iac for me and it does move.. it barely moves in or out... i cycle the car to the on position and it kicks out a fraction of an inch... you turn the key to the off position and it gos back out a fraction or so.. it is so small of an increment i didnt even notice it when i would turn the key on and walk back outside... shouldnt it move more or is this normal ???

 

Use Shoebox's guide to check it:

http://shbox.com/1/iac2.jpg

 

ok.. i took the iac off and took it to work where it checked within spec of shoebox's site, measure 50 ohms on both sets of contacts and no continuity where it shouldnt have.. but for some reason i didnt trust it, and my co-worker said to heck with it just defect it out and grab one of them off the shelf.. whats it going to hurt, so i did and now it is working fine.. is it possible to damage the pintle part of it to where it wouldnt work, while it still measuring the proper reading with an ohmeter? the reason i say this is my buddy was pushing on the old one while i was swapping the new throttle body onto the vehicle..

 

The pintle is not to be moved by hand on an old unit. It can be permanently damaged.

 

ok thanks... i thought that might be thr problem.. my buddy doesnt know how to leave things alone... thanks though .. your guides helped me out a ton