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Fd idle rises when coasting with the clutch in

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Old 10-21-21, 01:16 PM
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Fd idle rises when coasting with the clutch in

I’ve had this problem where if I’m coming to a stop and put the clutch in the rpm’s will stay at about 1500 and then drop to idle once I completely stop. Anyone have any clues what it could be?
Old 10-21-21, 01:55 PM
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I think this is intended, with stock ECU/PFC the car idles at 1200-1500 while rolling and settles back to 750 when completely stopped. I've heard it's to make it easier to get into gear or something while you're still moving.
Old 10-21-21, 02:50 PM
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Check the clutch switch and clean ISC.

Dale
Old 10-22-21, 11:24 AM
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Please provide details on the vehicle's engine mods.
Old 10-22-21, 11:54 AM
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This has been the case with almost every manual car I've ever owned.
I assumed its normal.
Old 10-31-21, 12:57 PM
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LOL maybe this explains my weird idle. It idles high, and sometimes hangs higher after extended freeway use. ABS is deleted. Maybe there's nothing telling the car I've come to a complete stop?
Old 10-31-21, 11:04 PM
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Dash pot working?
Old 10-31-21, 11:24 PM
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Originally Posted by mr2peak
LOL maybe this explains my weird idle. It idles high, and sometimes hangs higher after extended freeway use. ABS is deleted. Maybe there's nothing telling the car I've come to a complete stop?
The ECU gets vehicle speed from a sensor in the transmission, not the ABS system. That transmission speed sensor actually goes through the dash/speedometer/odometer which converts speed to a digital signal for the ECU. It's all spelled out in the factory wiring diagram, although it can be tricky to follow when a signal jumps from one page to another.
Old 11-01-21, 12:19 AM
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Originally Posted by billyboy
Dash pot working?
How would I check?

Originally Posted by scotty305
The ECU gets vehicle speed from a sensor in the transmission, not the ABS system. That transmission speed sensor actually goes through the dash/speedometer/odometer which converts speed to a digital signal for the ECU. It's all spelled out in the factory wiring diagram, although it can be tricky to follow when a signal jumps from one page to another.
Good to know, thanks, crossing things off the list
Old 11-04-21, 03:36 AM
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Originally Posted by mr2peak
How would I check?
More intended for the other bloke's symptoms, sounds peculiar that idle rpm would hang, but only while moving.

Process should be in the manual, if you download it, but that's not at hand for me at the moment. Typically when they stuff up, the push rod barely protrudes from the housing, normal is 8~10mm.
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