I recently changed out the engine in a 01 Altima.. Was bought with burnt motor. All connections are good.. the engine will turn over,,has gas in the cylinders, but will not fire.. Have checked all fuses, relays, etc.. There is not moisture in the distributor or any other apparent problems. I have a CP91856 code reader that runs the code check (no codes) all passed.. and have run all dianostics that it will run.. No matter what just no fire...

well i dont know what trouble shooting you've done but here is a good place to start,

remove the intake hoses all the way up to the throttle body, with some one cranking the engine spray starting fluid into the intake manifold, if the car starts then its a fuel delivery problem, if it doesnt then its a spark problem, this isnt true in absolutely all cases, but the majority of them,

if it seems fuel related, check your fuel pump relay, fuel pump, and fuel filter

if it seems spark related you can buy spark testers, which plug in line with the spark plug wires and will flash every time a pulse is sent through them, this will at least tell you if it is sending a current to your plugs,

also make sure its not something stupid, like the rotor is missing from inside the distributor cap, or something simular,

also check your spark plugs, they can tell a lot about an engine, if you pull one and its wet, then there is no spark going on,

well without having any more info , that is where i would start,

good luck

welcome to nico by the way

Thanks for the reply and the invite.. I have fuel.. do to when I pull one of the plugs after trying to crank they are wet with gas.. I have one wire pulled off the plug with another plug in it laying on the head.. There is not even a hint of spark.. All is normal in the distribitor, rotor etc.. It kind of appears that something such as security shutdown or this model has a special key with a chip, that has to match the computer.. This is what I'm being told...This is the correct key for the car, so still open to answers lol