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I've posted about this issue in the past. Car will drive fine for possibly days on end then suddenly it will hang idle at around 1500rpm when cruising or noticed when coming to a stop. Unplugging the IAC makes it go back down, or restarting fixes it.
I've checked for throttle cable binding, I've jiggled wires in the 10 pins and TPS when it happens, changed TPS....nothing other than a restart seems to clear it.
I'm currently having it remote tuned by Decipha, who is awesome and good to answer my stupid questions. He indicates that because the drive logs show a part throttle condition, that it is either a mechanical (cable binding) issue, a TPS issue or wiring problem. I tend to believe him as he knows his stuff.
Due to the intermittent nature of this issue I'm having a difficult time trying to diagnose. Wires will show continuity when checked.
Since it is so random, I can probably live with it, but if I can figure it out, all the better.
Looking for any ideas that I may not have tried yet.
Cheers.
 

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If you have a quarterhorse I'd hook up laptop with binary editor and monitor your TPS voltage. It might be heat related where the TPS acts up and the voltage goes up to 1.05 or something like that indicating throttle activity.
 

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Discussion Starter #3
Ya, Quarterhorse with TunerPro RT. I'll have to see if I can monitor TPS voltage with that. I have a log of it acting up so I can give it another look. Thanks
 

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I've posted about this issue in the past. Car will drive fine for possibly days on end then suddenly it will hang idle at around 1500rpm when cruising or noticed when coming to a stop. Unplugging the IAC makes it go back down, or restarting fixes it.
I've checked for throttle cable binding, I've jiggled wires in the 10 pins and TPS when it happens, changed TPS....nothing other than a restart seems to clear it.
I'm currently having it remote tuned by Decipha, who is awesome and good to answer my stupid questions. He indicates that because the drive logs show a part throttle condition, that it is either a mechanical (cable binding) issue, a TPS issue or wiring problem. I tend to believe him as he knows his stuff.
Due to the intermittent nature of this issue I'm having a difficult time trying to diagnose. Wires will show continuity when checked.
Since it is so random, I can probably live with it, but if I can figure it out, all the better.
Looking for any ideas that I may not have tried yet.
Cheers.
Sent you a message.
 

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The exact same thing just happened to me the other day. I had the laptop hooked up and notice the TPS voltage was above 1V at idle. I hit the throttle quickly in neutral to see if it was hanging. same thing, high idle around 1500RPM. pulled over and popped the hood while it was still running and tried tapping on the TPS and jiggling the wiring but it didn't change. It did return to normal after I shut it off waited a few minutes. I replaced the TPS with a spare and so far so good.

If you restart the car at the elevated voltage, the eec will zero it out and that's why it idles normal after a restart.
 

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MX8...is your swap harness one that was Mass Air factory, or a Mass Air swap?
Enjoy_The_Ride...same question: factory Mass Air or swap?
 
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