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The engine Idle's fine and runs good(a little rich maybe) but if you're shifting or coming to a stop, idle's around 1600 rpm's until
you come to a completely stop,then it drops down to normal. Even IF YOU THROW IT in Neutral while moving it will stay up.

Some suggestion's please !!!!!!

Thank's in advance !!
 

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The computer also keeps the idle up while moveing, usually not that high though.
 

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I'm having the same problem and actually started a new thread for the same problem as this. Maybe I should have noted I have no cats as a 93 and older is exempt. It only started doing this with the Ford idle plate, but without the plate, it will hunt and surge till fully warmed up.
 

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Well I do smell a bit on the rich side but I have been told you'll smell that way without cats, which I do not have. I run long tube headers and dyno max cat back system, no cats.I just wondering if there is another adjustment to the Ford idle plate I think I literally have the throttle plate closed so all the idle air is from the Ford idle plate.
 

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If you have ever turned the throttle stop screw, the issue is probably directly related to your altering of that scalar value in the tune by turning that screw.

Vacuum leaks/ deteriorated hoses

VSS sensor issue on the trans
 

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The engine Idle's fine and runs good(a little rich maybe) but if you're shifting or coming to a stop, idle's around 1600 rpm's until
you come to a completely stop,then it drops down to normal. Even IF YOU THROW IT in Neutral while moving it will stay up.

Some suggestion's please !!!!!!

Thank's in advance !!
do an engine running self test

i bet the ecm cannot control idle

as said, if you jacked with the throttle stop, you get what you have

and if you did jack with it, its because you had an idle issue already, and you thought you could adjust it.

without seeing commanded idle speed, when you it comes back to ‘normal’ you really have no clue if it is

commanded idle speed is changing all the time, it is rarely at one set rpm for long
 

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I just went through this with my 94 GT. My tuner thought it was my 65mm tb leaking extra air by. Well before purchasing a new TB, I changed out my IAC with a new ford IAC. Boom!!! no more hanging idle at 1600rpm. I believe the IAC was not closing fully. The idle drops when you come to a stop is the ECU pulls back timing when you stop is what my tuner explained. He actually made mine pull back to 5degrees to bring my idle down more until I could fix the problem. So get a new IAC and see if that helps. FYI..I tried cleaning my IAC and it didn't help. Good luck.
 

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that is an easy diagnosis before buying

unplug it.
 

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That's what I did, but it wasn't closing all the way so it still idled high. Even idled high after the whole idle procedure.
 
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