Good day,

My KJ 3.7Ltd engine light came on while driving on tar at a steady 40kph.

This happened about a week ago and the next morning when I started the vehicle the light went off again and everything was fine until today.

It came on with some rough idle and it stayed on. The OBD code is P0123 and refers to the throttle position sensor (TPS). Problem is; I don’t know where this sensor is located.

1. On the throttle body are two plugs. Which plug connects to the TPS the top or the bottom one?

2. Any suggestions on how to test the sensor or what the readings must be on the plug going back to the controller (once I can allocate it)?

_________________
My Rig:
2002 Jeep Liberty 3.7 Limited 4X4

Mods to date:
2" lift by fitting local manufactured stiffer coil springs
Duel battery system
Nudgebar
Frontrunner Towbar

Better rubber
** 245/70/16 Cooper ATR's **

I'll check when I get home tonight.
That part is very easy to change (about 5 minutes) and you can pick it up at your local auto parts store for around $35.


EDIT: Ok, I just noticed that you're in South Africa, so I don't know what the cost will be in your neck of the woods.

_________________
Take the road less traveled.

Thanks Edvalencia

Everything was normal again this morning when I drove to work.

When stoped at work, I’ve checked all the plugs around the throttle body. While juggling the wires that went to the sensors on the throttle body the Jeep started again with its rough idling and on went the engine light. It seems that it must be a loose connection or bad wire but I could not tell which one, since all the wires move along with the harness as you try moving one.

It will help a lot if I know were the TPS is

Does anyone know how to test the TPS or perhaps what voltage or current must flow in which wires (once one knows which wires went to it)?
Are there ways of testing the output on the plug once you unplug it

_________________
My Rig:
2002 Jeep Liberty 3.7 Limited 4X4

Mods to date:
2" lift by fitting local manufactured stiffer coil springs
Duel battery system
Nudgebar
Frontrunner Towbar

Better rubber
** 245/70/16 Cooper ATR's **

The Throttle Position Sensor is the top plug. The bottom plug is the Idle Air Control Motor.

The sensor looks like this:


I don't know hot to test it, but I believe it's a sealed unit, so you can't service it.

When it starts to go bad, the engine will run fine, then start to act up. The engine revs up, down or stalls. Even if you disconnect the battery, the light CEL will disappear and the Jeep may seem to run fine for a short while, but the problem will return.

As I said, it's very easy to change. Just unplug the wires, remove the two screws and it's out.

Good luck.

_________________
Take the road less traveled.

Many thanks for your assistance. It helped a lot.

Regards

_________________
My Rig:
2002 Jeep Liberty 3.7 Limited 4X4

Mods to date:
2" lift by fitting local manufactured stiffer coil springs
Duel battery system
Nudgebar
Frontrunner Towbar

Better rubber
** 245/70/16 Cooper ATR's **