1. Welcome to Jeeps.net!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Jeep discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Jeep owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

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

    Joined:
    Apr 7, 2017
    Member:
    #1305
    Messages:
    5
    Gender:
    Male
    First Name:
    Dalen
    Vehicle:
    Black 1993 Jeep Grand Cherokee
    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

    Joined:
    Jul 19, 2016
    Member:
    #2
    Messages:
    4,068
    Gender:
    Male
    Welcome! What are the symptoms?
     
    Dalen_Frederick5[OP] likes this.
  3. Apr 7, 2017 at 7:12 PM
    #3
    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

    Joined:
    Apr 7, 2017
    Member:
    #1305
    Messages:
    5
    Gender:
    Male
    First Name:
    Dalen
    Vehicle:
    Black 1993 Jeep Grand Cherokee
    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

    Joined:
    Oct 3, 2016
    Member:
    #317
    Messages:
    2,018
    Gender:
    Male
    First Name:
    Peter
    Houston
    Vehicle:
    1979 Jeep CJ7, 258, TH350, NP208
    Howell fuel injection, header, HEI distributor, TH350, NP208, SOA lift with YJ springs in the front & GW springs in the Rear. AMC20 with G2 1 piece chromos trussed, Dana 30 with G2 chromos and 760x ujoints and MM Stainless Hubs, Geared 4.56. Tom Woods shafts, Metal cloaks, Caged, 37" Toyo MTs.
    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.
     
    chris4x4 likes this.
  5. Apr 8, 2017 at 8:37 AM
    #5
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine Moderator

    Joined:
    Jul 19, 2016
    Member:
    #2
    Messages:
    4,068
    Gender:
    Male
    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
    #6
    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

    Joined:
    Apr 7, 2017
    Member:
    #1305
    Messages:
    5
    Gender:
    Male
    First Name:
    Dalen
    Vehicle:
    Black 1993 Jeep Grand Cherokee
    Awesome! I'll check all of them! Thanks!
     
  7. Apr 9, 2017 at 6:06 AM
    #7
    Dalen_Frederick5

    Dalen_Frederick5 [OP] Member

    Joined:
    Apr 7, 2017
    Member:
    #1305
    Messages:
    5
    Gender:
    Male
    First Name:
    Dalen
    Vehicle:
    Black 1993 Jeep Grand Cherokee
    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

    Joined:
    Apr 8, 2017
    Member:
    #1309
    Messages:
    87
    Gender:
    Male
    First Name:
    Jay
    Arizonia
    Vehicle:
    2014 Jeep wrangler unlimited wellys wheeler Black
    xrc front bumper 12000 pound badlands winch 6 pod lights fender flares kc headlight 285/70/17 tires 2 inch leveling kit bushwhacker air snorkel k/N intake rough country duuel steering stabilizer kit
    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

Products Discussed in

To Top