IAC sticking...effect on part throttle driving?

sunil6784

Member
Mar 31, 2005
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18
Boston, MA
This question is about my truck, but I think it would relate to most cars.

I know that the IAC valve on my 96 4.0 Ranger is sticking a little. Not enough to make it stall, but enough that it gives it some hesitation and bucking at idle every once in a while. I cleaned it, but it came back. I need a new one...

Anyways, since the IAC valve is partially sticking, does this effect performance/mileage at part throttle cruising? I havent noticed any difference except when the engine is coming just off idle.

Do computers monitor or account for air that is coming through the IAC valve at part throttle?
 
The IAC is essentially useless when the throttle blade is open any degree (a closed Throttleblade is a severe impediment to air flow to the motor, hence having a means of bypassing it).

The IAC will play into the dashpot function while moving and that's a time when I'd be worried if your idle is dropping too low or too fast (having a car stall while downshifting for a sharp turn, for instance, could really suck).

Good luck.