Wierd i know but my car is having problems idling.

The car runs fine, no loss of power, runs smooth but as soon as I stop, like to wait at a red light or something the problem starts.

It ticks over fine for about 10 - 15sec then starts going lumpy and the engine management light starts flashing. If i turn the car off and on the light goes off and the car runs fine again, although I still can't leave it on idling.

This only started happening a few days ago. I had a bit of a run with a 3.2 Audi TT up a big hill (left him, he wasn't happy) and it wasn't until i'd left the "private road" and got the to traffic lights the problem happened. The engine started to go lumpy and the engine management light was flashing, i limped away from the lights and had no power at all. I noticed I had no boost and my boost gauge was no longer working. Opened up the bonnet and the vacume pipe for the boost gauge had popped off. Put it back on and all was fine. Though ever since then, i continue to get the idle problem.

Also today while playing with the problem I think i made it worse. I left it going lumpy to see how long to would go on for and the engine management light stopped flashing and stayed on permenently. I won't go off even if I restart the car, although my caqr runs fine with it on.

Any ideas?