Hey i have a 2006 nissan 350 with the rev up and noticed my gaskets were leaking from the plenum so i chose to replace them. After taking off the plenum I realized the throttle body had build up so cleaned that with throttle body cleaner while it was detached as well as the MAF with MAF cleaner. After putting everything together the vehicle wants to crank but not start however was running fine besides the gaskets beforehand, could anyone help me out?

 

Check all of the wiring harnesses again. You might have not plugged one of them in all the way.

 

This... also there is a ground on the front of the car that is for spark. I accidently broke mine doing valve cover gaskets and had to fix it.