ECU reset

[Hicks]

Does anyone know what is reset on the engine when you do the 'reset' procedure - open the bonnet and door, then switch the ignition (but don't start the engine). You hear a high pitched whine for 30 seconds.

Reason I ask is that my car has been idling very rough, and yesterday it was hesitant even in 4th/5th gear. The reset has fixed this, but I know the problem will re-occur. Just seems strange that the reset fixes it for a while.

 

[1835harri]

i dont know about the engine, but i did mine recently and gave it a little rev when it was first started up and it was fine.
anything electrical..

 

[G2232]

the reset is for the trottle body is performs a re alignment but i believe it re-adjusts to suit your driving style

 

[DPJ]

There's also a recent thread proving this method doesn't work. You can only do it with Vag-Com.

 

[G2232]

well thats what i thought dave.
i had tried this a few times and never trusted that i did anything. the only thing i do with a reset is make sure i DONT rev for a few good minutes until ecu has taken a correct air reading from MAF
(not sure thats important but i've always done it)