My Girlfriend has just got a better car, It's a 1997 Mazda Astina hatch, Auto. Anyway it's all good except one little thing bothers me, when you are driving and pull up at a set of traffic lights the revs drop to about 3-400rpm and car feels like it's about to stall then the revs stabilise at the 800rpm mark. Any body have any ideas what may be the cause of this? It has only just started doing it as well coz never happend 3weeks ago when we test drove it.