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tps sensor

  • Thread starter Thread starter schwbs5.0
  • Start date Start date Oct 11, 2004
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schwbs5.0

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  • Oct 11, 2004
  • #1
how do you set your tps to .99 i was told my car was running to rich and that would fix it. i have volt meters and all that stuff i just dont know what to do..1988 Gt
 

Legendary

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#2
  • Oct 11, 2004
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I assume you know where it is. Well you loosen the two screws (slightly) that hold it and you move it clock-wise or counter clock-wise depending on where it's set now. Once you get it to .99 you tighten the screws. You might need an extra pair of hands to keep the volt meter on the wires while you adjust it but it's fairly simple.
 
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schwbs5.0

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#3
  • Oct 11, 2004
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thanks man
 
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92GreenGT

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#4
  • Oct 16, 2004
  • #4
Do I put my volt meter on DC or AC?

Not very electrical savvy.
 

jrichker

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  • Oct 16, 2004
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92GreenGT said:
Do I put my volt meter on DC or AC?

Not very electrical savvy.
Click to expand...

DC volts only.

Try this... Currently there is some dispute about setting it at .99 volts but anything less is probably OK. All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a Digital Voltmeter (DVM) to do the job.

The Orange/White wire is the VREF 5 volts from the computer: don't use this wire when you set the TPS.

You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS

Here’s a TPS tip I got from NoGo50

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .97v-.99v, the closer to .99v the better.

(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.
 

HISSIN50

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#6
  • Oct 16, 2004
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Joe, do you know if the puter zeroes out the TPS reading at start up (as long as it is not out of the adaptive and tolerance capability [perhaps +/- 25%])?

i have read yes and no, and also that SN 5.0 puters can, but ours cant, etc..... any insight or clarification?
 

jrichker

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HISSIN50 said:
Joe, do you know if the puter zeroes out the TPS reading at start up (as long as it is not out of the adaptive and tolerance capability [perhaps +/- 25%])?

i have read yes and no, and also that SN 5.0 puters can, but ours cant, etc..... any insight or clarification?
Click to expand...


The jury is still out...

I haven't heard a definitive answer from an authoritative source yet...
 

281pony

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Aug 31, 2003
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#8
  • Oct 16, 2004
  • #8
when your adjusting your tps voltage, should you adjust it to .99 with the key on but engine off? or with it idling?

i adjusted mine as close to .99 as i could with the engine off before and my tps voltage code went away. now its been a couple weeks and im getting a tps circuit failure. should i adjust it again with the engine running?
 

5LugFoxFanatic

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#9
  • Oct 16, 2004
  • #9
http://www.duggerracing.com/techtips/tps.shtml
 
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big_tiger15

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#10
  • Oct 17, 2004
  • #10
jrichker said:
DC volts only.

Try this... Currently there is some dispute about setting it at .99 volts but anything less is probably OK. All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a Digital Voltmeter (DVM) to do the job.
Click to expand...

My mines at 4.3 volts closed. I think I need a new tps sensor. lol but I grounded it by touching the throttle body.
 

HISSIN50

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#11
  • Oct 17, 2004
  • #11
big_tiger15 said:
My mines at 4.3 volts closed. I think I need a new tps sensor. lol but I grounded it by touching the throttle body.
Click to expand...
ya sure you probed the right wire?

Joe, thanks so much for the info. i figured if anyone knew, it was you.
 
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big_tiger15

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  • Oct 17, 2004
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well yea the green one... The wire already had a little hole from it being tested before. Would my battery only having 9.8 volts mess with it? lol that was a stupid question. I know its dying
 

Michael Yount

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#13
  • Oct 17, 2004
  • #13
From Charles O. Probst' book "Ford Fuel Injection & Electronic Engine Control" page 89 - "Recent Ford systems, all EEC since 1988, use a Rotary TP. The potentiometer increases resistance as the throttle shaft rotates. It is not adjustable, but the control-module programming compensates for any differences in sensors, readjusting to a base voltage when the throttle is closed."

Interpretation - set it where ever you like within reason (according to other data in the book between .6V and 1.3V). Each time you close the throttle the computer looks at the tps closed throttle setting and whatever voltage it sees gets re-established as the 'new' baseline TPS setting. Bottom line - setting the TPS at '.99 for better performance' accomplishes no change at all.
 

Michael Yount

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Oct 17, 2004
#14
  • Oct 17, 2004
  • #14
Bigtiger - measure ONLY between the green wire and the black wire - DO NOT 'ground on the throttle body'. It will likely read something below 1.0V. Open the throttle (engine off of course) and it should smootly and gradually increase up to between 4.0V and 5.0V at w.o.t. If you're reading 4.3V between the black and green wires with the throttle closed you either have a bad tps or a problem with the wiring harness or ecu. And it's a waste of time to run tests with a battery that's putting less than 11.5V into the system.
 

HISSIN50

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#15
  • Oct 17, 2004
  • #15
Michael Yount said:
Bottom line - setting the TPS at '.99 for better performance' accomplishes no change at all.
Click to expand...
Michael, you are starting to sound like S&2B's (he was always pretty funny in the way he shared those same sentiments).
 

Michael Yount

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#16
  • Oct 17, 2004
  • #16
"Michael, you are starting to sound like S&2B's"

Ouch! That one left a mark...
 

HISSIN50

"How long does it take to get help in here?
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#17
  • Oct 17, 2004
  • #17
Michael Yount said:
"Michael, you are starting to sound like S&2B's"

Ouch! That one left a mark...
Click to expand...
for real? i respect him - and it cracks me up how he tells people to not bother with the TPS dial-in. i laugh whenever i read that post.

anyhow, my comment was not intended to "leave a mark" - it was me trying to be cute first thing, after waking up.
 

jrichker

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#18
  • Oct 17, 2004
  • #18
Michael Yount said:
From Charles O. Probst' book "Ford Fuel Injection & Electronic Engine Control" page 89 - "Recent Ford systems, all EEC since 1988, use a Rotary TP. The potentiometer increases resistance as the throttle shaft rotates. It is not adjustable, but the control-module programming compensates for any differences in sensors, readjusting to a base voltage when the throttle is closed."

Interpretation - set it where ever you like within reason (according to other data in the book between .6V and 1.3V). Each time you close the throttle the computer looks at the tps closed throttle setting and whatever voltage it sees gets re-established as the 'new' baseline TPS setting. Bottom line - setting the TPS at '.99 for better performance' accomplishes no change at all.
Click to expand...

The definitive answer from an authoritative source has arrived... I stand corrected and educated....

Thank you Michael, I need occasionaly need some reminding to read and remember better...
 

Michael Yount

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Oct 17, 2004
#19
  • Oct 17, 2004
  • #19
"definitive answer from an authoritative source"

We all bow down to Mr. Probst....
 

HISSIN50

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#20
  • Oct 18, 2004
  • #20
jrichker said:
The definitive answer from an authoritative source has arrived... I stand corrected and educated....

Thank you Michael, I need occasionaly need some reminding to read and remember better...
Click to expand...
Me too, Me too!

thanks Michael.

one day i will learn as much as each of you two have forgotten.
 
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