1G TPS reads less then 5k ohms

[9!'clipseDOHC]

I was following the VFAQ to check my 1g TPS. It says pins 1+ and 4- should read 5k ohms. I checked 3 different TPSs and got 4.8, 4.7, and 4.0. Is this number adjustable (is there a way to make it higher) or if it’s low its low? Also how low is out of spec, meaning a bad TPS?

The second part of the TPS check, pins 2+ and 4-, I can get the 9k ohms just like the VFAQ wants (at least on the 4.8 and 4.7 TPSs, the 4.0 is on the car at the moment and I was unable to check it.

Any helps is greatly appreciated!

Someone (Steve) should really put together tech articles for these things.

 

[steve]

I've posted numerous times that the VFAQ is wrong, how to adjust the various TPS, and posted links to the factory manual. That should be enough to allow anyone to fish for themself.

The FSM says that the acceptable range of total resistance (pins 1 and 4) for the 1G TPS is 3.5k to 6.5k ohms and that the output voltage should be between 0.48 and 0.52 volts. It also says that the resistance between pins 2 and 4 should change smoothly in proportion to the angle.

It's because of this range in total resistance and the range of actual sensor power voltage from the ECU that the VFAQ is wrong. You can't just measure the resistance of the TPS output and set it. You have to measure the voltage or measure the total resistance and the actual voltage across pins 1 and 4 then calculate the correct resistance for a voltage divider using those parameters to get the correct resistance.

On a 2G the IPS is inside the TPS sensor. The same resistance tests apply but it's the IPS switching point that is used for adjustment and the acceptable output voltage is so broad that is doesn't matter except for really broken TPSs.

 

[9!'clipseDOHC]

Thank you!!