2001 Nissan Altima car sputters

I think you may have an intake gasket problem. I had the same problem in my 2001 Altima. Its a problem a lot of Altimas have, or will get, unfortunately. The car felt and looked like it was ready to die whenever I came to a stop. The needle would drop to zero and then catch itself and go back up suddenly right before stalling. The engine has to be taken apart to get to this thing and thats where all the money is going to be since the gasket part itself isnt all that much. I spent $575 fixing this but the car ran smooth and fine, like it should, once it was replaced. By the way, the auto shop I took the car to did not know what it was. They did some tests on it and then wanted to replace half the engine for $1500. I found out exactly what it was from a forum like this one and cut the bill by more than half!
They called me when the replacement was done and said, "you were right, the car drives smooth now!"

Thank you so much. We haven't fixed the idling problem yet, but my husband checked the remote key set up in the dash, and that was the problem with the ignition wanting to stay on. One of the connections was not connected all the way.