I swear I searched, just can't find a straight answer.

I just replaced the battery obviously because the other one died. The car turns over really good but will not crank. ecu problem..? Fuel..? I checked the MAF it looks clean... Im out of ideas and I hoping I don't need to take it to Infiniti...

Not that I think it makes any difference, but just to throw it out there I am using a spare key for the first time... Not sure if this has anything to do with it.

Any help would be greatly appreciated!

 

It was the key...

 

how did the key cause the problem?

 

He probably used the spare key to start his car? Or one of the fobs with no chip inside.

 

Thats correct.

After doing some research I found out, if while the engine is trying to crank the security light stays illuminated the key is not "learned"...

Used the regular key and it worked.