What would cause a 2000 Nissan Maxima to turn over but not start?

I had the same problem with my 2000 GXE...it just died suddenly..I used a hand held scanner and it turned out to be a camshaft position sensor about $ 80.00.It's very easy to replace,it's located on the front cylinder head. Looking at cylinder head (near the radiator)follow the camshaft location (with your eyes) towards the left,you will notice it on the side ,it only has one bolt and one wire plug. very simple fix. I hope that this is your problem. Good luck. jal1948@aol.com