ok so my 93 runner 3vze motor has been idleing around 1500rpms when warm, its not the cold start as it revs even higher when cold, i adjusted the idle screw, sweet now she idles around 7-800, but it surges.. will jump up to 1200 or so then back off immediately... i should mention that it did this bfore it turned the idle down, but not as extreme... my question is... would a vac leak cause this? it was my understanding that a vac leak would make it idle low.. also..any tips for finding this possible leak would b extremely helpful

 

A vac leak could cause this, yes.. It could make it idle high, surge, or maybe idle low if it upsets the mixture just enough.

You can't see or hear most small leaks - you need to spray to find em

 

ya, i tried to spray starting fluid around the intake, nothing, should i use something else? The intake is coming off tomorrow anyway, as i need to do my knock sensor, hopefully ill find something then