95 mustang gt 5.0 high idle 1,500 rpms

Discussion in '94-95 5.0 - Specific' started by hottwheels04, May 18, 2014.

  1. hottwheels04

    hottwheels04 Well-Known Member

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    Just Noticed my Idle has been to high, when I first start the car it jumps to 2,000rpms then comes down car runs good sits at 1000 rpm but after a while driving idle hangs at 1500 to 2000 rpms I looked for a vaccum hose leak couldnt find it I just dont want to have to get it retuned for that not sure else could cause it bad iac? I claned the connectors and maf. Not sure what else heres a picture of it idling


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  2. Michael Plummer

    Michael Plummer Active Member

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    Unplug your IAC? Does the rpms come down to normal? If yes, then your TPS voltage is to high. How to correct? Get engine up to normal operating temperature (195- 200 degrees), and perform a base idle rest for 94/95 cars.
     
  3. Rallim

    Rallim Active Member

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    Would that help with a hanging idle? My car will usually jump to 1500-2000 then fall to where it's supposed to idle, just really slowly.
     
  4. hottwheels04

    hottwheels04 Well-Known Member

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    what do I need to do to do a base idle reset ?
     
  5. hottwheels04

    hottwheels04 Well-Known Member

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    I found this

    What is needed?
    - Flathead screwdriver
    - You'll also need a wrench to remove your battery cable

    How to do it
    1. Disconnect the battery's negative terminal to reset/clear the computer's memory. Leave it disconnected for 30 minutes. WARNING: Whenever removing your battery cables ALWAYS disconnect the negative battery cable first and reconnect it last. Otherwise you could destroy your computer or cause a battery explosion.
    2. Disconnect the plug going to your idle motor which is located on the front of your throttle body.
    3. Reconnect your battery's negative terminal.
    4. Start the engine, and set the idle to the rpm you want with the stop screw on the bottom of the throttle body.
    5. Turn off the engine.
    6. Reconnect the plug on the idle motor
    7. Make sure all accesories (radio, blower motor, a/c, lights, etc) are off and start the engine.
    8. Let engine run for two minutes.
    9. Turn engine off and wait two minutes then restart engine and let idle for two minutes with all accesories on.

    EDIT: This article refers to "stop screw" on the throttlebody. We have noticed that on 94-95 (and probably 96-up) Mustangs don't have a stop screw but have a small piece of "threaded rod" (A) instead. This threaded rod can easily be turned with a pair of pliers to do the adjustment stated above. There are pictures below of this "threaded rod". Also note that the stop screw on fox body Mustangs are in the same basic place as the picture below (A)