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IAC valve?

Discussion in 'Cherokee' started by Dalen_Frederick5, Apr 7, 2017.

  1. Apr 7, 2017 at 3:39 PM
    #1
    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

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    Okay so I just replaced my iac valve on my 93 grand Cherokee 5.2 about 4,000 miles ago. It worked great and was the problem. Then my tranny went bad and I had to get a new transmission.
    Ever since I got a new tranny it's been doing ALL of the symptoms again. But the iac valve is still in great shape since I literally just replaced it! Is it the iac?? Do I have to get another one?!?
     
  2. Apr 7, 2017 at 6:55 PM
    #2
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine Moderator

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    Welcome! What are the symptoms?
     
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  3. Apr 7, 2017 at 7:12 PM
    #3
    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

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    Well on a cold start it starts just fine and idles at about 900 then at operating temperature start it revs to like 900 but immediately drops to like 200 (super low) then back up to about 500. Then if I put it into reverse or drive or turn the wheel towed the curb (because I park on a hill) it wants to stall. All seem like symptoms of bad iac. Which is only a couple months old. But like I said it all started just a couple days ago after I got my new tranny
     
  4. Apr 7, 2017 at 9:22 PM
    #4
    OFFGRID

    OFFGRID Well-Known Member

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    It could be 1 or multiple sensors. It bypasses computer until operating temp is reached, then the computer takes over at normal operating temp. Tranny is a big job. Make sure all. Vacuum hoses got hooked back up.
     
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  5. Apr 8, 2017 at 8:37 AM
    #5
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine Moderator

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    That's what I was thinking. Maybe a vacuum hose wasn't connected or was broken during the transmission repair.
     
  6. Apr 8, 2017 at 10:56 AM
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    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

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    Awesome! I'll check all of them! Thanks!
     
  7. Apr 9, 2017 at 6:06 AM
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    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

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    Okay so there was actually one vacuum hose that was slightly loose and one vacuum hose that had a gaping hole in it. I tightened that one and replaced the one with the hole in it, but I'm still having just as many symptoms as before. Couldn't find anything else. I have a theory (and it could be completely insane) that when I put in the new iac before, the computer "got used to it" and when the battery terminal was disconnected to put the new tranny in, the computer still "thought" I had the old tranny in even though the new tranny might be putting a little bit more load on the engine causing the IAC to not be providing enough air to the engine thus the stalling. Like I say it could be completely out there but it's all I got
     
  8. Apr 9, 2017 at 7:59 AM
    #8
    K6puppy

    K6puppy Well-Known Member

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    Hi it could be a few things do you have any codes you checked for vacuum leaks you look for any pinched or loose wires if you do not find any thing try this disconnect both battery cables touch both battery cables together this will drain all power from computer hold cables together for 5 min reinstall cables start jeep hold idle at 1500 to 2000 rpm in park then 750rpm in drive about 1 min each range or if you think it is iac try tapping it with hammer if you need further help let me know
     
    Last edited: Apr 9, 2017
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