engine idle issues after IAC replacement

[bobthesuper]

Hello everyone, this my first post so please forgive my mistakes. I have a 1998 Tahoe with 118,000 miles on a 350 vortec, automatic, 4 WD. It was starting to stall occasionally after start at idle. A friend said it was probably the IAC, so I replaced it (my first time doing something like this). Now it has a high idle and occasionally surges at idle. My research says it could be a vacuum leak but I'm kind of lost at this point. Ant help would be greatly appreciated! Could the vacuum leak be at the IAC? The new one had an O ring.

Thanks,
Bob

 

[95Escahoe]

Did you follow the correct install process? On the TBI ones there's a few steps you need to go through not sure about the Vortec ones

 

[bobthesuper]

The procedures listed on the instructions were pretty simplistic, mostly disconnecting battery, removal and reinstall. I read on the web something about adjusting the plunger depth but it looked correct. I think it his not seating properly causing a vacuum leak. I'm going to try a new O ring. Does their computer need time to adjust to the new part?

 

[Horns]

Check for a leak first. Take a sprayer with water in it and mist around parts of the engine. If the idle changes, you've found a vacuum leak.

-via Mobile

 

[95Escahoe]

On the TBI ones you need to adjust the pintle if it's out to far, then when it first starts up its gonna idle high and go down then you have to shut it off, start it up then drive for a few miles can't go past 25? Forget what, not sure how the Vortec ones are

 

[bobthesuper]

Thanks everyone. I will btry the water spray trick. I remember trying to adjust the pintle but it didn't seem to want to move. Is it threaded? Or how do I adjust it?

Thanks again!

 

[95Escahoe]

On the TBI ones you just turn them if I remember right