idle problems
#1
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Year: 99
Model: Cherokee
Engine: 4.0
idle problems
I have a 88' Cherokee with a 97' engine and ever since i got it running it idles fine for probably 20 seconds or so then the idle gets rough and low for about 5 or 6 seconds then back smooth again. It doesn't usually crank up the first time I hit the key and it seems to get better when at normal operating temperature. What should I check?
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Year: 1998
Model: Cherokee
Engine: 4.0
I have a 88' Cherokee with a 97' engine and ever since i got it running it idles fine for probably 20 seconds or so then the idle gets rough and low for about 5 or 6 seconds then back smooth again. It doesn't usually crank up the first time I hit the key and it seems to get better when at normal operating temperature. What should I check?
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Year: 1998
Model: Cherokee
Engine: 4.0
Yes, it's on the throttle body and held by two screws. Not sure how to test it, my guess is that you could check resistance through the coil, but not sure you will be able to determine if it's functioning properly. I would just remove the two screws, pull it out, remove the oring, and spray it with carb cleaner, and reverse procedure. Mine was pretty dirty with a lot of black deposit. After cleaning it, the idle settled. The way the valve works is that the system feeds it a certain amount of current causing it to open or close, the part that you are cleaning acts as a valve to increase or decrease the amount of air allowed to enter the throttle body, when dirty, it's not a good seal. If your idle is still erratic after you clean it, it could possibly be that the coil inside the valve could be wearing out and that causes the valve not to hold steady...so it is moving in and out therefore causing your idle not to be steady...hope this helps.
#7
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Year: 1998
Model: Cherokee
Engine: 4.0
If you have tuned up everything else, it could be a bad IAC. Not sure how to test it, but assume you could hook it up to a variable power supply and should hold steady at a set voltage.
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#9
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Year: 1998
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Keep trying...you'll find it...
#10
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Year: 99
Model: Cherokee
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I took the throttle body off when I cleaned the IAC and cleaned the valve and where the valve seats really good. I don't have a/c right now.
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