97 3.4L 4Runner Throttle Position Sensor

[salijema]

Hi all,
My wife's 4Runner (auto) has been stalling/dying very intermittently. I've searched and there seems to be many suggestions to solve this problem. No check engine lights. I hooked up the scanner yesterday, and there are no codes in the history. However, the throttle position sensor indicated a position of 11.9% when closed, and 76% when fully open (this is opening and closing the throttle at the throttle body). Is that right? On all my other cars, the TPS indicates 0% when closed, and 100% when wide open.
I then check the resistance between the appropriate connector pins at the TPS in the closed and open postiions, and the measurements fall within the range in the service manual, albeit on the low end.
Has anyone found this to be a problem, especially in relation to the intermittent stalling problem?
Can just the TPS be replaced, or is it an integral, matched part of the throttle body assy?
If just the TPS can be replaced, is this available as aftermarket (Pep Boys, Kragen, etc), or is a dealer-only part?
Thanks for your patience,
Jim

[4Wheel]

Originally Posted by salijema

I then check the resistance between the appropriate connector pins at the TPS in the closed and open positions, and the measurements fall within the range in the service manual, albeit on the low end.

If the measurement at the TPS terminals fall within the factory spec and you followed the procedure exactly then I would doubt the "universal" scanner reading.
Depending on the scanner, cheap to high end they are NOT all the same. AutoZone may be willing to use different model then you can compare the results.

You have the empirical data, as long as your methodology is not suspect.

[salijema]

Hi 4Wheel,
Thanks for the info. I'm using the same scanner (bought from http://www.obd-2.com/) on my other vehicles, and the throttle positions read 0% at closed and 100% at open. Anyways, I bought a TPS from Toyota ($65), and compared to the original, and got same results, both from the scanner readout and in terms of the resistance readings.
Still looking for the answer to the intermittent stalls.