iac gurus, is mine bad?

[86turbo]

hey guys ill make it quick...

horrible cold start, tries to die. ect and act resistances are good. I also have a slow surge that travels from 750 to 1200 and back again. I unplugged my iac and it limited the surging to only 100 or so rpm. Stays under 1k rpm now at idle. Voltage across the iac leads show 1.5v+.2v and never varies to anythig different even when the car is stone cold. btw no codes being thrown for the iac...

thanks

Drew

 

[93 LX]

http://forums.stangnet.com/698148-help-me-create-surging-idle-checklist.html

 

[86turbo]

yeah man i know about the list, ive seen you post that same link in 3 threads tonight. I already did all of the checks for the iac and i need some advice form someone who has diagnosed a bad iac. The voltage across the leads never changes, when its cold Or hot and the idle doesnt seem to change when i unplug it.

Anyone?

Drew

 

[jrichker]

If it surges without the IAC being connected, the IAC is not the problem. A working IAC can amplify a surge caused by other faults. Using a DC voltmeter across the IAC will not give a correct measurement of what is really happening..

IAC operation:

 

[86turbo]

thanks again for the reply!!

"""I unplugged my iac and it limited the surging to only 100 or so rpm."""

i forgot to mention i have a stage 1 cam, typical h/c/i setup .....

You dont think the iac could be causing the majority of the surging and another small problem could be contributing?? It only surges like 100 rpm with the iac unplugged and its a slow surge..

 

[noslow1986]

i bought mine new at autozone and my car still had cold idle issues i turn the iac upside down and it runs alot better no more cold idle issues. dont know why but it works maybe somebody can explain that to me

 

[86turbo]

thanks again for the reply!!

"""I unplugged my iac and it limited the surging to only 100 or so rpm."""

i forgot to mention i have a stage 1 cam, typical h/c/i setup .....

You dont think the iac could be causing the majority of the surging and another small problem could be contributing?? It only surges like 100 rpm with the iac unplugged and its a slow surge..

 

[jrichker]

Fix the problem with your MAF, and the idle surge will probably go away.

 

[86turbo]

first off i really appreciate you giving me advice...

I installed a known good iac (other car) and the idle is a lot better now.

I'm trying to figure out if my maf voltage is good or not, i assume you're saying its not