Hello, I have a 1996 Nissan Maxima with approx. 160k miles.

Recently, it has been stalling whenever I am at a stop light or in idle. The rpms go high than low and eventually to zero than the car just shuts off. It usually starts right back up but sometimes it takes longer to start. I have replaced the fuel filter. It happens sporadically, not everytime I am stopped. I thought the problem was bad gas so I let the gas I thought was bad mostly go out than I put high grade gas in it. I have no idea what the problem could be and it's so frustrating because as a single parent, I need my car to work so I can get to work and school and take care of my child. The last car I bought prior to this had the same problems but that was due to a cracked engine block. Any suggestions on what I could do to fix this problem or any idea on what the cause could be? Thank you in advance.