Occasional start up stall and bad a/c idle -IAC?

[240sxinlv]

On my 95 240sx KA every tenth time I start the car the revs will go up like normal and then drop to 0 and stall. Also with the a/c on the idle is a bit to low.

I think I have narrowed it down to the IAC.

I have noticed there is the IAC Valve and the IAC Regulator -

http://www.courtesyparts.com/b....html

Any idea which is more likely bad (other then saying "replace both")

Thanks!

[WWJD]

on start up my SOHC did the same thing. I sea foamed my car, changed fuel filter. then I took apart the iav iac and cleaned them with wire brush and brake cleaner. problem gone for me