corsa ls hi-torq idle control valve

[x14sz_ed]

not too sure if the problem i have is the idle control valve, but would anyone know how to test for a knackered idle control valve, i think this is the problem or there is a problem with the idle control valve but not too sure, i have been told i could test it with a multimeter but dont know what to look for and which pins to put it in on the connector plug, the car when cold cuts out a hell of alot and works better but really underpowered when moving from traffic lights or junctions, also doesnt pick up as well as it used to through the gears and struggles up hills, dont know about egr valve either because dont know where it is on my car, but have been told to test it,i have had the car linked up to the diagnostic computer at college and it didnt come up with anything, the car has done 104,800 miles is on a p plate and at 96,000 had head gasket and thermostat done, dont know if the information i have given will be any help but advice and any thoughts would be grateful thanks.

[x14sz_ed]

have also been told it could be the egr valve but dont know were it is, would any of you guys know were it is thanks