Wierd signal from Volvo Bosch TPS

[The Billiam]

When I turn the key to my car to the "run" position(not running or cranking) and push the gas pedal, the throttle position gauge on megatune does not move. I used the "calibrate TPS" tool anf got an idle value of about 220, and a WOT value of about 100. Now when the throttle is at idle, MT says 100%, and at WOT it jumps to 0%-nothing in between.
What's happening?

[fscott]

Actually, your TPS is. You've got it wired backwards. You should see a higher value at WOT than you do at idle.

[bobnova]

If this used to be a Bosche LH jetronic car (all volvo 2.3's, as far as i know), the TPS is just two little microswitches, one that is turned on at full throttle, one that is turned on at idle.

If this is the case you will need to swap a variable resistance TPS on from another car.

[gezpacho]

Hello, I am converting my 85 740 to msII, also I am new here.

Is there a known part # for a direct tps replacement, or is there a make/model known to use a suitable replacement?

Thanks the help is much apreciated.

Juan

[blarf]

If this used to be a Bosche LH jetronic car (all volvo 2.3's, as far as i know), the TPS is just two little microswitches, one that is turned on at full throttle, one that is turned on at idle.

If this is the case you will need to swap a variable resistance TPS on from another car.

The TPS from the LH-Jetronic 3.1 cars (mostly 90s 240 manuals) was of the potentiometer type. LH 3.2 cars (850 non-turbos, but those won't bolt right up) too.