TPS issues (cont)

[Ebme Geek]

Hopefully this might help as Throttle Position Sensor seems to come up at regular intervals on here, so thought I would do a couple of measurements for reference...

First of all, this is how mine show up as ok on the tacho, pic taken this morning before I went to work
[smg id=2465 type=preview align=center caption="TPS Tacho 5k"]
When I first checked mine after doing my cam chain I thought this was just a fraction high so thought I would tweak it down a touch,
First lesson learnt - > This is ok and in the acceptable range, drop below the range and the needle drops straight to '0', be a fraction above the range and it jumps straight to '10'; so I should not have touched it  :rolleyes
Second lesson - > The adjustment is very sensitive and easy to move as you tighten the screws.

Anyway back to the main bit - >
The TPS is just a potentiometer so first check the track resistance, Haynes spec this as 5 KΩ +/- 1.5kΩ
I used some test clips to get onto the two outer contacts
[smg id=2466 type=preview align=center caption="TPS Track resistance"]

Then I checked the resistance from one end of the track to the 'wiper', this at idle position
[smg id=2467 type=preview align=center caption="TPS res Idle"]

Then at Wide Open Throttle (WOT) position
[smg id=2468 type=preview align=center caption="TPS res WOT"]

The actual figures may vary quite a bit, hell the tolerance on the track is +/- 30%.
But another important bit is that as you move the throttle from idle to WOT the reading should smoothly and consistently change, there should not be any drop-outs or blips, this is a little easier to see with an analogue meter (that is one with a needle)

And finally just to show the wires
[smg id=2469 type=preview align=center caption="TPS wires"]