it sounds like the idle control valve,it controls your throttle for you so you don't stall when idling (ticking over) it can go haywire and make you car rev like crazy.if you locate your throttle body,its on the right side of you engine,the air pipe from your air box goes into it.there is the throttle linkage on the front (facing the radiator) and the idle control valve on the other side connected by an electrical multi plug,take the multi plug off and unscrew the 2 torx screws holding it in,soak the valve with petrol or loads of wd40 and it should be okay from then. let me know if you need more help and how it goes page793@btinternet.com
richard
October 2008
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