Every so often my 92 will idle real high. I can usually put it in nuetral or park and it will idle back down but when I go back to drive and excelarate slightly it will idle high again and stay there. It has a fuel injected 351 in it.Any ideas? I was thinking maybe the IAC valve?

 

Could be a sticky IAC.

 

Is there a way to clean them or do I just need to replace it?

 

You can try cleaning it. Use WD-40 and work the plunger with a screwdriver.

 

Will do. Thanks allot

 

I cleaned the IAC valve and it seemed fine even before I cleaned but my truck still idles high and hangs there some. If I stop and hold my foot on the brake it will eventually idle back down but will idle high again as soon as I take off. Yesterday when it did it the battery light came on and the baterry gauge was almost pegged out on high. Could my alternator be going out and my computer is making my truck idle high to compensate? Any ideas guys?

 

Get the alternator tested/repaired/replaced before you fry something. Start by reading these captions:

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If the brake pedal affects the idle, it's possible the brake booster is bad. It's very easy to replace. At idle, listen near the pushrod under the dash for hissing.

 

If it's associated with putting your foot on the brake, it could be a vacuum leak in the brake booster.