I've had this problem for about a year now but haven't done anything about it as it hasn't effected anything else, I don't think. What's happening is that when I turn the key, the car turns over but immediately the revs drop. Then, the revs either drop to 0 and the car turns off, or the revs drop to almost 0 and then raise back up and idles normally. Every time I turn the car on I always tap the gas to make sure the revs stay up and not turn off. I have a couple other problems that might have something to do with it. The 'boot open' warning light comes on every so often, even after I open and close it several times. The other is a red light flickers behind the headlight dial when turned on.
Any help would be much appreciated!!

 

Hi.
Sound like a throttle valve issue. Would start by having the throttle valve re-adapted to the engine ecu. This would normally only need to be done if the battery had been disconnected\gone flat. The engine ecu then loses the learnt values of the throttle valve positions (idling right up to full load). A vag scanner with this function would need to be used. I would say the other faults are unrelated.