TPS (Throttle Position Sensor)

[creslevi]

Replaced my TPS 2/6/08 worked fine till about 6/2/08
When I started car the engine would race, refused to idle and service engine soon light came on, If I unplug the TPS it idles fine, Question Are there any other sensors in that circuit that feed it information, or do you think I was just unlucky enough to get a bad replacement, I got it at Car Quest ?. It's on a 94 Buick LeSabre 3800. Thanks.
Rick

[HotZ28]

Does the spring return on the TPS seem to be working? Have you tested the voltage on the blue wire with ignition on?

[creslevi]

Hi
Thanks for the response, Yes the TPS does seem to rotate with the throttle shaft, No I haven't checked any voltage, I have been sick the last month with Heart problem, and can't get out to the garage (too weak) I am driving it with the TPS unpluged, But have no cruise control or passing gear, just trying to evaluate the problem ?.
Rick

[happydog500]

When I replaced my TPS, it started dong what you discribe 6 months later. I reset the code, it ran fine.
Try clearing the code and plugging it in to see what happens.

I think mine did it twice, once more almost a year later. I just reset the code and it has been fine ever since (couple years?).
Chris.

[creslevi]

Thanks for the suggestion, as soon as I am able I will give it a try, I think you just unhook the battery a few minutes to reset the codes ?.
Rick

[inafogg]

i think on your car u would be ok since its OBD 1 but not on obd 2 systems (96 & up)of course using a scanner is always best.Good Luck & hope u recover soon!!

[happydog500]

Mine is OBD 2, even overnight didn't clear the codes. I had to use a scanner. the other post said OBD 1 is different, so it might work.
Chris.

[creslevi]

I tryed clearing the code, Service engine soon light went out but the engine still raced
Rick

[creslevi]

Blue wire is .06v, i forget what it should be ?, This thing has always been soo dependable I am shocked to have this problem in 6 mo after paying a shop $195.00 to read & clear the codes and install the new sensor $80.00, They said they also replaced the throttle body gasket ?.
Rick

[HotZ28]

Blue wire is .06v, i forget what it should be

That is too low, it should be around .45v and no more than .50v! What is the idle rpm? Are you sure the T/B is closing all the way?

[creslevi]

As soon as I unplug the TPS it returns to normal Idle speed, What might cause the high Voltage ?.
Rick

[HotZ28]

You should now check the grey wire, (PCM reference voltage) it should be 5.0v. If this checks out, I would suspect the TPS is at fault. BTW, are the TPS mounting screws tight?

[creslevi]

Yes the screws are tight, I will try to check the grey wire today sometime.
Thanks Rick

[HotZ28]

While you are at it, check the low voltage again. Your previous reading does not correspond to a high idle condition. If the reading on the blue wire @ idle position is actually .06v, the engine would probably not run at all.

[creslevi]

I don't have a grey wire, mine is kinda blue, with engine idling it say's 5.5v with it plugged into the TPS, I shut it off and restarted several times and so far it idles fine, but at this point don't know how long it will last ?.
Rick