hi all just got my vectra c 150 sri cdti and when im driving and take my foot off the throttle to slow down in gear,when i put my foot back on the throttle to speed up i can hear a plastic popping or quiet knocking sound ,its only when in gear and driving and seems to be comming from in front of me in the engine bay fairly close to the bulkhead (i think )
any ideas on possible causes please
thanks darron
loving my veccy though (it almost sounds like a plastic flap moving on throttle take up )