why cant i adjust my tps?

94gts

Member

Jul 4, 2004

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0

16

Carmel, New York

Jul 20, 2006

#1

• Jul 20, 2006

• #1

so my car is still sitting in pieces because i hit a deer a few weeks ago so when i get bored i find things to do. well today i decided to check my tps and for some reason it is at 5.01V closed and does not budge even when i move the blade. the reading also does not move when i move the sensor either. yes the key was on and the car was off. What gives ?

 

1TallMF

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Apr 17, 2006

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Montreal

Jul 20, 2006

#2

• Jul 20, 2006

• #2

You are probing the wrong wire. That is the 5V refference voltage from the computer. On the TPS connector, the top wire is ground, the middle is the signal, and the bottom is refference voltage. You want to probe the ground and signal wires. It should be anywhere between 0.6 - 1.0V, but not higher. It is arguably pointless to adjust the TPS on our cars.

However, if you actually were probing the two top wires, and seeing 5V there, then something is deffinetly wrong.

 

1slow95

Founding Member

May 16, 2002

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ohio

Jul 20, 2006

#3

• Jul 20, 2006

• #3

Yeah, it sounds like you're just on the wrong wires.

Also, I don't think it's pointless to adjust the TPS. Mine was waaay off(reading .5v) and I was having some strange problems with the car that were probably TPS related. But, as long as it's between .9 and 1.0, I don't see any reason to adjust it.

 

1TallMF

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Apr 17, 2006

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Montreal

Jul 20, 2006

#4

• Jul 20, 2006

• #4

I thought I read somewhere that the 94-95 computers read the TPS voltage at startup and automatically refferenced that as being 1.0V, for example, if the TPS value at startup is 0.9V, then the computer would add 0.1V to the entire operating range, so a part-throttle value of 2.55V at the sensor would convert to 2.65V to use as a value in the load tables. Maybe I'm totally off my rocker on this one, but I coulda sworn one of the fine chaps on here explained this before.

 

Stanger007

Founding Member

Sep 26, 2001

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46

Baton Rouge, LA

Jul 20, 2006

#5

• Jul 20, 2006

• #5

That's been my observation by watching my twEECer is that the EEC sets the voltage at startup and automatically sets the TPS to 1v.

My Fox (A9L EEC) wasn't like this - had to manually set the TPS w/ a voltmeter.

 

1TallMF

New Member

Apr 17, 2006

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Montreal

Jul 20, 2006

#6

• Jul 20, 2006

• #6

Thanks for the backup info, 007. I was hoping I didn't just pull that out of my @$$


:SNSign: FTW

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

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129

Jul 20, 2006

#7

• Jul 20, 2006

• #7

The fox TPS does internally zero-out upon start-up as well.

 

94gts

Member

Jul 4, 2004

873

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16

Carmel, New York

Jul 20, 2006

#8

• Jul 20, 2006

• #8

1TallMF said:

You are probing the wrong wire. That is the 5V refference voltage from the computer. On the TPS connector, the top wire is ground, the middle is the signal, and the bottom is refference voltage.

Click to expand...

ah **** me. i guess i was wrong to assume that the wire with the black was the ground. dumb ford

 

bill302

Active Member

Nov 2, 2005

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alabama,gadsden

Jul 21, 2006

#9

• Jul 21, 2006

• #9

So to test a 94-95 car you would put the negative lead on your voltmeter to a good engine ground or the first grey wire. Then you would put the positive voltmeter lead to the middle grey with white stripe wire. If you need more help look at the image below...copied from link below...

http://www.muscularmustangs.com/tps.php