My truck is cranking but not starting
I have replaced icm
good spark
40psi at fuel rail
valve pulse using diode
in time using both static timming and pulled cyl. Number 1 barred over and set to 0
new map sensor
won't fire even with start g fluid

 

If it won't start with starting fluid, then your problem is not fuel delivery, it is spark. You say you have spark but is that at the plug or the coil?

 

at the plug on all cylinders.

 

Could it have jumped time?

 

I took the cap off the distributor and pushed down on my crankshaft bolt and it took close to a quarter of a turn before the cap started turning.

 

Uh, yeah, that sounds like too much slack in the chain to me. I am thinking you need to replace timing chain and gears.

 

It is also possible that the cam bolt got loose and broke the cam dowel pin. Had this happen to my motor in my pulling truck, same exact symptoms as described in this thread, crank but no start and backfires. You will have to take the front cover off and take a look.