Because the quad drive module is in the ecu.
Its what controls the idle motor etc etc.

First, check the engine earths.

i need 2 b sure before spending loads on a new 1? how can u b sure its the ecu

knacked ecu

ive got a 1995 corsa sri that just will not idol, every time i let off the throttle it cuts out and has started to chuck a big flame out when changing at high revs. ive had it diognistic tested and there is a fault with the quad driver module/control.

jus need to know what it is.

thanks