OK wtf... *TPS Issues*

[Imprezive]

So, I've started to poke around trying to figure out why my legacy has such a bad idle and spotty acceleration.

I've began to think its the TPS. And since I have a few FSM manuals I decided to test my TPS and compare it to the specs in the FSM. I usually don't get a CEL but sometimes I'll get a random Code 31 Throttle Sensor.


So, I first tested the TPS unit itself because it was the simplest to do.

To keep this thread simple I'll first throw out one test between Terminals 2 and 4 on the TPS.

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Fully closed it should read 1 Kilo Ohm

Fully open it should read 4.3 Kilo Ohm

(Value should smoothly increase in response to throttle valve opening)
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I'm getting about 8.6 kOhms when closed and around 3.4 kOhms when fully open. I've also tested another older TPS from a turbo model and got the same approximate results.

WTF!? Is the FSM wrong or is do these TPS's routinely wear out in this fashion?

If anyone has any data they have gathered I would greatly appreciate it!

[vrg3]

What FSM are you using?

The ones I have say that the resistance between pins 2 and 4 should move smoothly from 10-12 K down to 3-5 K as the throttle moves from closed to open.

What you're reading is close enough.

[Legacy777]

He's probably using the info from the 90 FSM

http://www.main.experiencetherave.com:8 ... sting1.jpg

[vrg3]

Huh. I wonder if that's a misprint in the 90 FSM... The TPS is the same for all years, and the 92-94 manuals I have match the resistances I posted.

In any case, Imprezive, I think your readings are fine.

[Imprezive]

Cool, thanks.

I have several different FSM's. The one I was reading out of WAS the 1990 Model Year book, but like Vikash says, it shouldnt matter.

I have also seen the same values in a chilton's legacy manual, as well as in one of my other FSM's.

I have the regular blue and white manuals. What do yours look like vakish?

[vrg3]

Blue and white, too. But I only have the 92 manuals, plus the 93 and 94 supplements.

[Imprezive]

Ahhh, so I just checked the same section for the 1991 FSM and it read the same of what you had vikash.

So it seems as if there was a misprint.

[vrg3]

Huh. Funny... I wonder where those numbers came from originally.