Test the 165 Throttle Position Sensor

Why do I want to test my Throttle position Sensor?

If your car won't start or you have a problem, or you have error codes that you are using to track down a fault, then you can eliminate or identify the throttle position sensor as your problem using this test procedure.

In particular if you have an idling problem you may want to test this sensor as it informs the ECU that the car is at idle.

I have also found that misalignment of this sensor may also cause misfires at wide open throttle.

For additional pictures click here

How do I test it?

On the right hand side of the throttle body is the throttle position sensor. Unplug the connector to it - it just pulls off. Make sure you pull it via the plastic housing and not the wires - you don't want to introduce faults! The pins for the sensor are now exposed and can be tested.

What's next?

Take your multimeter, set it to "Resistance Ω" and test between the following connections. Insert a feeler gauge to accurately measure the 0.5mm and 0.7mm distances between the stop crew and throttle position.

TPS is attached to the side of the throttle body Testing the TPS TPS connector pin out ECU Pin out article here

Clearance between lever and stop screw Between terminals... Resistance kΩ
0mm VTA - E2 0.2 - 0.8
0.5mm IDL - E2 < 2.3
0.7mm IDL - E2 Infinity
Fully open VTA - E2 3.3 - 10
n/a VC - E2 3 - 7


What if the readings I get are out of specification?

You can adjust the readings you obtained by loosening the 2 securing screws attaching the sensor to the throttle body. Very slowly move this until you obtain the correct reading. It is very fiddly but can be done. If your readings are way out then I would suggest concentrating initially on the resistance readings at 0.5mm and 0.7mm.

The other adjustment is via the stop screw located on the left hand side of the throttle body. Do not adjust this unless you have messed around with this previously...

That didn't work!

Oh dear, you are going to have to get a new one from Toyota or a scrap yard...