Ok,
I just got done swapping motors out on my F4i (the old one's block had cracked at the right front motor mount bolt, so its time to get it welded). Well, i got the new one put in (actually used). At first, it started an ran for about 2 minutes, at first it ran like the old one, then it started to run a bit rougher then it finally quit (it sounded like it started to skip an misfire right before it quit). soo... I tried startin it back up.. nothin, then it backfired. After that nothing else. Sooo. I replaced the main wiring harness and computer... still nothing. It just Cranks w/o attempting to fire over. Any thoughts from you guys?

Soo what it boils down too.
Tip over sensored has been BYPASSED
Fuel pump is Running like its supposed to
Started cranks, but motor will not run.

All the connectors are connected... except for one (its a 2 wire flat connector) its black in color, and i believe it has a green and black wire at it. I have looked high an low for any possible place for it to go, and i haven't found anywhere....

Any help is greatly appreciated. Also when i replaced the motor, i replaced the throttle body assembly with it also.

 

check the plugs? maybe fouled?

 

nope, haven't checked em, but i will in the afternoon.. i'm tired of f'n with it