QX4 shift

[don5154]

My friend has a 1999 QX4 w 98K miles. The transmission delays shifts into top gear. The dealer diagnosed it as the TPS and therefore not covered under the extended power train warranty. My Question: Is there a TPS in the transmission or is it the Throttle Position Sensor.

I have replaced throttle position sensors in other cars. No big deal if you know how adjust them. I don't know how to adjust this one. Maybe set to contact at a certain PRM?

[jtesensky]

The TPS is the throttle position sensor. There is a turbine sensor though, that might be what they are reffering to. They really should be adjusted by the factory so the check engine light can be reset.-Joe

[don5154]

Thanks jtesensky

Check engine light is not on. We thought we had a power train warrenty, however, it does not cover parts that are not lubicrated. So dealear wanted $350 to fix. I think that turbin speed sensor is lubricated. Could the TPS cause this problem? The car is a 1998 QX4 not a 1999.

[Q45tech]

The transmission tcu uses the TPS voltage [0.4-4.4 volts] as a 10 step indication of how far the throttle is pushed......the higher the voltage the more load is assummed and thus the higher the rpm is when upshifts occurr.

Fairly common failure [worn spot on potentiometer] ususally sets a code though.

Factory extended warranty or after market?

[don5154]

Thanks Q45tech After market warranty. Fine print excludes electrons. How does one adjust a new TPS on this car? This TPS has two connectors. Can I use an ohm meter + tach to setup. Is there also a micro SW that tell the ECU the throttle is at idle?

"They really should be adjusted by the factory so the check engine light can be reset."

Joe Do you mean the turbine sensor or the TPS?

I really appreciate you guys help.