I was reading this and got the jist that we can read the TPS voltage through the dianostic termial. Can we, and if so which terminal's is it?

https://www.thirdgen.org/messgboard/...ML/007593.html

Edit: This is for my '85 IROC TPI

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1989 Pontiac Firebird Formula LO3 Auto
-180 degree stat
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-vinyl security shade, velcro t-top bag
*****Possible summer '01 mods*****
Dual Snorkle, Auburn Posi, Keyless Entry, Wonder Bar from my IROC, 4th gen seats, T/A tail lights

http://www.geocities.com/krt80/

[This message has been edited by Keith5 (edited April 07, 2001).]

 

That article refers to trouble codes, not TPS voltage, although the ALDL will pop a code for a faulty TPS, (21 or 22). To read the TPS voltage, it has to be done at the TPS harness, at the throttle body. Take two sewing needles and pierce the insulation of the top two wires of the TPS harness. Then clip the leads of a Digital Voltmeter to each needle. Turn your key to ON, and read the voltage. If it reads in the negative, just reverse the leads. It should be at .54v (+/- .075v) with the throttle blades completely closed, and should rise smoothly to just over 4.0v with the throttle all the way open (WOT). If it is jumpy or doesn't rise as you open the throttle, then the sensor is bad, just replace it.

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Kevin Irving
85 Trans Am WS-6, 305 TPI, custom burned '86 PROM with '87 "165"ECM, Accel Supercoil & 8.8 Wires, MSD 6AL, Aluminum Driveshaft, Wonderbar, TB Coolant Bypass, Ported Plenum, Modified MAF, Syclone Fuel Pump, JET Airfoil

15.556 @ 86.65mph, Nov 10, 2000.... I know it sucks.. but it will get better!

http://www.geocities.com/transam85tpi/

Member - The Tidewater Trans Am Club, Norfolk VA http://www.geocities.com/ttacva/

 

Yeah, the post was about Trouble Codes, its just that TPS also got mentioned. If you want to read TPS via the ALDL, you need a scantool.

To find out more about adjusting your TPS, go here: TPS

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'97 Bonneville SSE

 

My fault... I didn't even take into consideration the scan tool.. Thanks B.

 

I know how to set it at the TPS. I just wanted to know if two of the terminals of the ALDL could be used to get the voltage.

 

Nope, but like GM Tech said if you have a scanner then it would be able to read it for you through the ALDL.... otherwise you have to do it at the TPS harness.