After doing a few maintenace things on the engine. eg cleaning throttle body , isc, replacing oil pressure switch, i reset the cpu and took the old girl for a drive. However now the car is changing gears funny and i cant get it to accelerator downshift. Nothing was wrong before i did this so i am wondering if anybody has had this happen. It is driving me nuts

Hey buddy

Well, seeing as you were doing some work in this area... and considering the role it plays in the automatic transmission's functioning... i would be having a good hard look at the thottle position sensor (TPS).

It's a penti-whatever-meter that sits on the trottle body. Depending on the position of the throttle butterfly, it reports a different voltage to the ECU.

Lol, im sure the background info is of little interest and you want to know how to test it?

At a closed throttle position, the TPS should be reporting around 0.98V. At wide-open throttle, it should be reporting 5v.

It sounds like it's doing nothing at all - so have a good look at the wiring to the TPS - it's mounted on the throttle body, so the wiring is fairly easy to see.

Well... that's a start anyway!!

Thanks mate

I have my brother dropping my multimeter over this arvo so i will check that.
I didnt take notice when i pulled the tb apart with the TPS, is there a special way to set this up when you put this back on. I notice that the butterfly turns the pot in the sensor, does this go on without tension or does there need to be tension on the pot

Thanks mate

My step father has a junker el that i ripped the tp off and just feeling the movement in it i could tell mine was stuffed, so i threw the good one at it and i am back to normal. It still has a slight rough idle but i amm using the ideas from here to figure that one out too.

After resetting the ECU you have to 'train' the tps, there's a method for doing this somewhere in the forums, it only takes about ten minutes and is crucial for the transmission to know when to change.

In fact, here it is:

NOTE DO NOT TOUCH THE ACCELLERATOR DURING ANY PERIOD OF THE ADAPTIVE PROCESS.
The correct way to set idle speed after battery disconnection is:
1. Run engine until operating temp reached and thermostat opened.
2. The engine should then be idled for approx 1 minute in each of the following conditions (total idling time approx 4 minutes)
3. Neutral with all electrical loads OFF.
4. Neutral with Air conditioning ON.
5 Drive with all electrical loads OFF.
6. Drive with Air conditioning ON.

After all this has been done then proceed to go on and to do these steps which actually set the TPS values;

5. *To set the closed throttle reference position, place the transmission
in Drive, Air con off, and let the engine idle for a minimum of 1 minute.
6. Next, set the wide-open throttle reference position by turning the
engine off- but leave the ignition switch to the "ON," position, ie;Idiot lights on etc, then press the accelerator
pedal to the floor and hold it their for 1 minute, minimum.
7. Then Place the gear selector to Park and switch off the ignition.
8. Drive the vehicle and check for proper shifting patterns.