Replacement IAC
#1
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Year: 1995
Model: Cherokee
Engine: 4.0 HO I6
Replacement IAC
I've been having a rough idle issue, revs high at start up and settles down when put into gear, then sputters at red lights or whenever shifting back into neutral. TPS was replaced and I took off the IAC and cleaned with spray and tooth brush. That helped a little but the issue was still there. Went to Autozone to swap out the IAC. New IAC is noticeably different from the existing one. Swapped them out and the Jeep idled really high at startup (2000-2500rpm) and would only settle down once it was put into gear and started rolling.
Pics attached, replacement IAC on the bottom (Duralast) and OEM (I think) on the top, you'll see the OEM is much longer. Do I need to be looking for a different brand IAC? Coincidently, I put the original IAC back in and Jeep now idles at around 500-700rpm but with the same rough idle issues as before, surging and occasionally stalling out.
Pics attached, replacement IAC on the bottom (Duralast) and OEM (I think) on the top, you'll see the OEM is much longer. Do I need to be looking for a different brand IAC? Coincidently, I put the original IAC back in and Jeep now idles at around 500-700rpm but with the same rough idle issues as before, surging and occasionally stalling out.
#2
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Maybe there should be something more direct in the sign-up process explaining to posters to fill out what they have? 44 posts and nada...?
Nothing personal RJ. It's just continually frustrating. I don't fully understand the IAC motor. It does move that deal (pintle),in and out. Of course no one has any clew what you happen to have, but on an 87-90 Jeep the fourth relay back, the "latch relay" might provide power to the IAC after shutdown so the IAC can re-set for the next start.
Some TPS's are adjustable and others are not...."Sputtering" can be a lot of things.
Nothing personal RJ. It's just continually frustrating. I don't fully understand the IAC motor. It does move that deal (pintle),in and out. Of course no one has any clew what you happen to have, but on an 87-90 Jeep the fourth relay back, the "latch relay" might provide power to the IAC after shutdown so the IAC can re-set for the next start.
Some TPS's are adjustable and others are not...."Sputtering" can be a lot of things.
#3
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What yr XJ?
Looks like the wrong IAC to me. Tip and shaft diameter look different.
Your oem IAC sounds like it's working fine. Idles where it should. Checked for any tripped codes?
Looks like the wrong IAC to me. Tip and shaft diameter look different.
Your oem IAC sounds like it's working fine. Idles where it should. Checked for any tripped codes?
#4
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Year: 1995
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Engine: 4.0 with all of the noise and clatter
That Auto Zone part looks like a cheap piece of crap. As far as your rough idle, have you done any tune up work to the engine?
#6
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Year: 1995
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Engine: 4.0 HO I6
Maybe there should be something more direct in the sign-up process explaining to posters to fill out what they have? 44 posts and nada...?
Nothing personal RJ. It's just continually frustrating. I don't fully understand the IAC motor. It does move that deal (pintle),in and out. Of course no one has any clew what you happen to have, but on an 87-90 Jeep the fourth relay back, the "latch relay" might provide power to the IAC after shutdown so the IAC can re-set for the next start.
Some TPS's are adjustable and others are not...."Sputtering" can be a lot of things.
Nothing personal RJ. It's just continually frustrating. I don't fully understand the IAC motor. It does move that deal (pintle),in and out. Of course no one has any clew what you happen to have, but on an 87-90 Jeep the fourth relay back, the "latch relay" might provide power to the IAC after shutdown so the IAC can re-set for the next start.
Some TPS's are adjustable and others are not...."Sputtering" can be a lot of things.
#7
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Year: 1995
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Went back to the shop twice to confirm the part number was correct. Next step is to order a OEM part or at least one that's higher quality than Duralast. No Check Engine light and no codes.
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#8
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Agreed, I'll be returning the part. Only other work I've done to the engine was to clean the throttle body, replace TPS, and add new spark plugs.
#9
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In my opinion, replacing the spark plugs without replacing the wires, distributor cap and rotor is just a waste of time. The plugs are not the only wear items in the ignition system. Heat and 40k volts, then the act of pulling the wires off of the plugs really takes a toll on them.
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Plug the new one in, (with the old still on) start it, turn it off. Now see if the pintal cranked in. The Iac is a motor that will leave that wherever it was when power to it was cut. You should fill out your info
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