850 Potentiometer

Volvo's price is (wait for it) £540+vat ish- depends on exact year and spec etc...(!!!)

Why do you think your ECU is broken? Have you blown it buggering around with something else? The Fenix units are normally very reliable. (as are the Motronic and Jetronic units on other 800/70 series cars)

Assuming your in the UK, have the ecu checked by atp electronics at one of their test stations

Tim..

mechanic that this might be the problem. Typically when just starting to accelerate from idling the revs fall away. Also, when decelerating towards a stop the engine sometimes cuts out. Thanks again. Tony

You need to read any stored trouble codes to begin with, and check the ignition switch contacts, and main relay as it sounds alittle like the ECU is loosing power when the car cuts. These are both known problems.

With an ECU either they work, or they dont. Very very rare to have intermittent running problems with them.

Other than that, check the vacuum line from MAP sensor to throttle body. and map sensor connector.

Tim..

" Tim (Remove NOSPAM. Registry corupted, reformated HD and lost alot of stuff :("

And to add- it would also be wise to check inside the ECU box for water ingress and corroded pins in the base.- pull up the locking lever and remove the ECU to examine.

Tim..