TPS

[rodalt02]

I have a rebuilt ECM and a new IACV to put in my 2001 Maxima. I am going to disconnect the motor mounts, since this is what destroyed the ECM in the first place. The place that rebuilt the ECM says that I have to install a new TPS along with the ECM and IACV to fix the problem and insure the warranty. Is this necessary? Does a TPS cause the IACV to fry the ECM? Also, how hard is it to replace the IACV and can a novice mechanic like myself do it? Thanks for all of your help.

[loystock]

You have agreed to replace the IACV and TPS to keep the ECM warranty. Otherwise, you are on your own. So it depends on how much money/risk is involved. Which is more expensive - the refurbished ECM or having the TPS and IACV replaced? In your earlier postings, I believe you have been given a link to the FSM. Also, instructions on how to clean/replace the IACV is in the FAQ 'sticky' within this forum as well as in the earlier threads that you have been to.

The TPS is just a sensor to provide the ECM with throttle position for fuel metering. In addition, it also has a WOT sensor (to TCM) and Closed sensor (to ECM). A defective TPS should not fry the ECU.

The IACV has a stepper motor whose driver is inside the ECU. A short in the IACV will definitely fry the ECU/driver. So you better check the motor resistance from the 6-pin IACV connector - Pin 2 (red wire) to either Pin 1 (white/Purple wire) or Pin 3 (yellow wire) should be @ 20 ohms; Pin 5 (red wire) to either Pin 4 (yellow/black wire) or Pin 6 (gray/blue wire) @ 20 ohms. Also check for any short to ground. If the resistance measurements are good, and assuming you have disconnected the connector to engine mount, then it is safe to install the ECU.