I own a 96 Altima, everything has been good until recently. It has begun to act up. The rpm drops drastically every now and then. It evetually drops to 0 and the car shuts off! I try to start it up again it is just wont stay on! I starts running, goes up to 1000 rpm and then shuts off again. I tried gasing it to help it stay on, but it does not work. Does anyone now what the problem might be?