Well my friend has a 1990 f150 with a 5.0; he decided one day to do a compression check, so he finished put everything back together like is was ( or so he thought) went to start it back up it would crank but not fire. So after cranking her over for about 10 minutes it started to catch one cylinder at a time and black smoke was pouring out of the exhaust. So after idleing for a while tried to put in in drive it started to pop and died. Tried to start it back up and wouldn't then after another 5 minutes of cranking it started. It will idle as long as u want but as soon as u put a load on it will die. Any ideas Im clueless.

 

Check out the MAP sensor vacuum line for being off or cracked open.
No map vacuum fuels the motor really heavey and fouls the plugs.
Usually a compression test is done with the throttle wide open. This causes no vacuum to the MAP and fuels to injectors heavey.
Next time, crank the motor with a shunt switch accross the starter solenoid and not use the ignition key. When you use the ignition key, the injectors fill the cylinders with gas.
On a motor already filled with gas, putting it all back togather and attempting to start, puts even more in on top of it = loooong crank times, run-down battery, overheated starter.
Sound like it's familuar?
Good luck.:santa:

 

Yea ill have him check it