I have a 93 GMC Jimmy the likes to stall out on me in the most inconvenient times, it idles really bad like it wants to die on me , I have asked a few mechanic buddies of mine what it could be , they said to check the hei module , I did and the prongs that plug into the distributor were rusted , I cleaned it and so far it has not stalled but I still have the idle issues, would changing the hei module help at all ? And what else could possibly be ?
My car has an automatic transmission.
It sounds like you may have a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your idle air control valve.
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