Ok guys, hopefully this is an easy one, I have a pretty good idea I have a bad IAC, but I thought I would put it out here for feedback as well, as there are very knowledgeable folks here.
My daughter has a 1998 Escort ZX2 with the 2.0 DOHC engine, 160K or so on the clock. I am very impressed with how good this car runs, even with the mileage it has on it. Been a good car to date.
Now that it is nasty hot and she is running the A/C, she let me know that twice now she has been sitting at a light and the engine has stalled with the AC on. She shut the AC off restarted the car and went on her way. The car runs fine at any other time cold or hot.
I checked it the other day when I was messing with a loose fan blower plug and noticed that when you turn the AC on the compressor really drags the motor down and the car does not idle up to compensate for the additional load on the engine. The car starts fine and idles at a pretty smooth 1000/950 range until you kick on the AC compressor, then it drops to 5-600 and runs pretty rough but will continue to idle very low in neutral.
I found a picture on another forum of the IAC and removed it today to clean it. Problem #1, there was no gasket in place between the valve body and the intake.....I am assuming the previous owner screwed with it too. I cleaned it with carb/tb cleaner even though it really wasn't horribly dirty. Problem #2, I pushed down on the top of the bellow portion inside the IAC and it only went down approximately 1/4 of the way and seemed to stop or jam at that location. I cleaned it and then sprayed some spray lube into it and tried to push the bellow down to "free it up". I am not sure if this bellow should collapse all the way freely or not, but hers would not.
I reinstalled the IAC back in the car -still with no gasket- and tried the car again. the car idles fine, seemed to initially rev to 1100 rpm and then immediately came to 1000/950 and stayed there idling smoothly until I turned the AC on and as soon as the compressor kicks in the rpm's dropped and the engine still will not compensate for the load. I did not find any loose hoses or anything, but didn't look that hard. I noted nothing else in the engine compartment that would cause this issue.
I checked our local auto parts stores online. 1 store says $70, the other says $125. I don't want to waste $125 of her money, or mine, throwing parts at this thing. But I am pretty darn confident it is a bad IAC Valve.
Anybody want to chip in their .02 cents on this?
My daughter has a 1998 Escort ZX2 with the 2.0 DOHC engine, 160K or so on the clock. I am very impressed with how good this car runs, even with the mileage it has on it. Been a good car to date.
Now that it is nasty hot and she is running the A/C, she let me know that twice now she has been sitting at a light and the engine has stalled with the AC on. She shut the AC off restarted the car and went on her way. The car runs fine at any other time cold or hot.
I checked it the other day when I was messing with a loose fan blower plug and noticed that when you turn the AC on the compressor really drags the motor down and the car does not idle up to compensate for the additional load on the engine. The car starts fine and idles at a pretty smooth 1000/950 range until you kick on the AC compressor, then it drops to 5-600 and runs pretty rough but will continue to idle very low in neutral.
I found a picture on another forum of the IAC and removed it today to clean it. Problem #1, there was no gasket in place between the valve body and the intake.....I am assuming the previous owner screwed with it too. I cleaned it with carb/tb cleaner even though it really wasn't horribly dirty. Problem #2, I pushed down on the top of the bellow portion inside the IAC and it only went down approximately 1/4 of the way and seemed to stop or jam at that location. I cleaned it and then sprayed some spray lube into it and tried to push the bellow down to "free it up". I am not sure if this bellow should collapse all the way freely or not, but hers would not.
I reinstalled the IAC back in the car -still with no gasket- and tried the car again. the car idles fine, seemed to initially rev to 1100 rpm and then immediately came to 1000/950 and stayed there idling smoothly until I turned the AC on and as soon as the compressor kicks in the rpm's dropped and the engine still will not compensate for the load. I did not find any loose hoses or anything, but didn't look that hard. I noted nothing else in the engine compartment that would cause this issue.
I checked our local auto parts stores online. 1 store says $70, the other says $125. I don't want to waste $125 of her money, or mine, throwing parts at this thing. But I am pretty darn confident it is a bad IAC Valve.
Anybody want to chip in their .02 cents on this?
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