What exactly decides that there's a fault with the car? is it the ECU? or is there a seperate dedicated fault finding machine thingy? and is there actually two TPS's??

there is a TPS on the throttle body in your engine bay, and there are 2 accelerator position sensors on your pedal box. These 2 sensors sense the position of your accelerator and send a voltage signal to your ECU, which then controls the throttle butterfly in your throttlebody, and the TPS on your throttle bodysenses the position of the butterfly.

They have replaced the sensors on the accelerator and the engine, and the PCM (ECU, Engine Management Unit, whatever tickles your fancy) so the next thing I'd be checking would be the wiring.

I have had a few of these on territorys. The throttle plate sticks due to flashing inside throttle motor housing flaking off. Throttle sticks then goes into guard mode dropping cyls and holding throttle. Tell em to pull a complete throttle body off a new car and put it on yours for you to drive and monitor.

Hi all

Thanks again for the interest in my problem...

To summarise what has been done to the car in order to fix this problem...

Throttle Position sensor has been changed on both ends the engine side and the pedal.

The computer has been changed as well

All fuel settings have been reset

Twice I have had the car at different dealerships where they have kept it for several days and hooked it up to the error / fault code reader, unfortunatley it won't do it when it is with them.

They tell me they can see a fault code in the black box that indicates a throttle problem but there is no other codes that lead them to the cause.

Once I turn the car off and restart the problem is fixed. Unfortunatley that is when I loose the codes out of the black box.

Cheers

Birdman

The above problems that I have mentioned have also been an intermittant problem. Cycling the key resets the throttle body to its start position and problem goes till it sticks again. that's what the click noise is at the throttle body when you turn the ignition on. If its not the throttle body then it has to be wiring fault considering you have replaced all the components at question.