I have an 83 f-150 with 351M, and i was running it the other day, brought it home and when i went to restart it, it wouldn't fire at all, no sparks! So i replaced the battery (which i killed trying to start it) the coil, cause i couldn't get a spark from the original,(that didn't work by the way )then i was told it could be the ignition module so i bought one of those, and now it will spark, but only after we stop cranking the motor over, like right after i get 1 big spark. (nothing coming from the plug wires either by the way. Please someone help me with this one. It sounds like a truck that is out of gas. (but it isn't, ya can smell it flooding)

 

Sounds like you have a wiring problem with no power to the ignition module in crank mode.

 

Yea.. Turn the key on then take a test light to the wires going in and coming from the ignition module... If you got power going in then check the Votage Regulater, they can ground out sometimes. If it doent start still have some one peck on it while you crank it.. if it starts then, its bad..come back and let me know how it turns out..