I have a 2001 Altima with 46k. It cranks and cranks, but will not turn over. Can you please advise me of some items I should look for before going to the mechanic. Thanks

did you find the answer to your problem ? I have the same problem.

Hi, does the engine turn over or not. if engine turns over see if you have battery voltage to the ecm relay. Had one spent weeks on it found broken white/blue wire at splice below batt in harness.

i think is a problem with the ignition cylinder...if u are still under warranty bring it to the dealership. it could also be a "pass-lock" feature gone bad if your car is equipped with it.