RPM's Dropping...?

Discussion in 'Fox 5.0 Talk' started by impulse001, Apr 8, 2008.

  1. impulse001 New Member

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    So when I idle my car, the RPM's drop to around 650, and as its sounding like it's going to shut off, they shoot back up to 1000/1100.. Drives fine, and if I give it some gas it will stop doing it for a little, but then start again.

    I took out the throttle body a few days ago to clean it, could It have something to do with that?
    impulse001, Apr 8, 2008
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  2. bloopbloob New Member

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    codes. did you change anything with the tps or iac? could be a lot of things. dump the codes.
    bloopbloob, Apr 8, 2008
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  3. 5.0Droptop Neutered Member

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    Did you replace the alt yet? If not its running on low voltage it will make it act strange.

    Taking the TB off could have messed with the idle settings and TPS settings.
    5.0Droptop, Apr 8, 2008
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  4. Mustang5L5 Founding Member

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    Reset the idle.

    Unplug the IAC and let the engine idle. Adjust the idle using the idle stop screw to bare minimum idle (the lowest it will go while letting the engine idle)

    reset the computer

    plug IAC back in

    start car and let it relearn idle strategy
    Mustang5L5, Apr 8, 2008
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  5. 5.0Droptop Neutered Member

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    word...

    Check tps while at it....Test with digital volt meter, Use the black wire as ground green wire is positive. Set it to .97-.99 volt. To adjust it loosen the 2 screws and turn + or -
    5.0Droptop, Apr 8, 2008
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  6. mustangfan1990 New Member

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    my car does the same thing and I have tried every trick in the book. I finally got mine fixed when I got mine tuned
    mustangfan1990, Apr 8, 2008
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  7. fiveohwblow Mustang Master

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    +1. The other ways mentioned will fix manual problems but I have had the same issue both before one tune, and after another. Point is it can be tuned out if your tuner knows what he is doing.
    fiveohwblow, Apr 8, 2008
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