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TPS-Idle set

  • Thread starter Thread starter 87GTee
  • Start date Start date Dec 20, 2003
8

87GTee

New Member
Nov 8, 2003
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Dallas,TX.
Dec 20, 2003
#1
  • Dec 20, 2003
  • #1
Maybe somebody could explain this to me,I've tried to get the tps set @ 0.95 to 0.98 and i can get it to stay the only problem is my idle won't go any lower than about 850rpm's.I've reset the computer after the initial setting of the tps by disconnecting the battery and still nothing,by the way the tps is new from ford dealer.Somebody please lend me their expertise on this.
thanx.
 
J

jerry beach

Founding Member
May 20, 2002
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Ocala,FL
Dec 20, 2003
#2
  • Dec 20, 2003
  • #2
Thats not a bad idle, be prepared to live with it and thank your lucky stars its not surging. You cant reallyadjust idle manually. There is an idle setting proceedure, and it varies a bit from year to year. I have the proceedure for my 88. It worked once, but now I cant get it to take again to stop the surge. Mine idles at 850-900, higher when cold, as high as 1400 till it warms up. It takes 5min or so to warm up.

Try setting you TPS at .85v. See if that shortens the pulse width a bit. Its worth a try. It really has made no difference where I set mine. Do a seach on posts by Michael Yount. He has some good info on idle setting proceedures. Look at the similar threads at the bottom of this page.
 

Mavrick

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Aug 29, 2002
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Collingwood, ON
Dec 20, 2003
#3
  • Dec 20, 2003
  • #3
http://www.corral.net/tech/maintenance/idlereset.html
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Dec 20, 2003
#4
  • Dec 20, 2003
  • #4
87GT - are your throttle body and iab solenoid completely clean and free of build up? If it won't idle properly or low enough, it's often because the iab solenoid has built up oily sludge in it over the years -- part of the pcv design produces this side effect. If it's clean and functioning correctly, the idle ought to come down to the factory setting of around 675. If you've got a factory tach, they're notoriously inaccurate. If that's what's reading 850 - it could simply be off. Use a calibrated shop tach to check it. Lastly, don't set the tps above .95V. The system thinks it's not idling if it sees above 1V, and getting that close seems to throw some of them off. Jerry's right - .85V-.95V is fine.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Dec 20, 2003
#5
  • Dec 20, 2003
  • #5
87GT - are your throttle body and iab solenoid completely clean and free of build up? If it won't idle properly or low enough, it's often because the iab solenoid has built up oily sludge in it over the years -- part of the pcv design produces this side effect. If it's clean and functioning correctly, the idle ought to come down to the factory setting of around 675. If you've got a factory tach, they're notoriously inaccurate. If that's what's reading 850 - it could simply be off. Use a calibrated shop tach to check it. Lastly, don't set the tps above .95V. The system thinks it's not idling if it sees above 1V, and getting that close seems to throw some of them off. Jerry's right - .85V-.95V is fine. Lastly, are you sure the throttle stop is set correctly? Back the screw out away from the throttle linkage, insert a .003" feeler blade and tighten the stop until it just touches the feeler. Then remove the blade and tighten the stop another 1/4 turn. That puts the blade at the factory setting. TPS should be set engine warm, not running, ignition on. And disconnect the battery after all that to clear things out. Give it some time - it may search around a bit as you drive it for a day or two.
 
8

87GTee

New Member
Nov 8, 2003
20
0
0
Dallas,TX.
Dec 20, 2003
#6
  • Dec 20, 2003
  • #6
tps

Michael Yount said:
87GT - are your throttle body and iab solenoid completely clean and free of build up? If it won't idle properly or low enough, it's often because the iab solenoid has built up oily sludge in it over the years -- part of the pcv design produces this side effect. If it's clean and functioning correctly, the idle ought to come down to the factory setting of around 675. If you've got a factory tach, they're notoriously inaccurate. If that's what's reading 850 - it could simply be off. Use a calibrated shop tach to check it. Lastly, don't set the tps above .95V. The system thinks it's not idling if it sees above 1V, and getting that close seems to throw some of them off. Jerry's right - .85V-.95V is fine. Lastly, are you sure the throttle stop is set correctly? Back the screw out away from the throttle linkage, insert a .003" feeler blade and tighten the stop until it just touches the feeler. Then remove the blade and tighten the stop another 1/4 turn. That puts the blade at the factory setting. TPS should be set engine warm, not running, ignition on. And disconnect the battery after all that to clear things out. Give it some time - it may search around a bit as you drive it for a day or two.
Click to expand...

Thank you for the help that you offered,I'm going to give this a try tomorrow,I've got a headache and my wife's bitchin.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Dec 20, 2003
#7
  • Dec 20, 2003
  • #7
87GT said "I've got a headache and my wife's bitchin."

My experience has been that those two symptoms are often related to, and/or caused by one another.
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
1,785
1,130
233
Indiana
Dec 20, 2003
#8
  • Dec 20, 2003
  • #8
Michael Yount said:
87GT said "I've got a headache and my wife's bitchin."

My experience has been that those two symptoms are often related to, and/or caused by one another.
Click to expand...

Yes Indeed....
 
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