Could it be a faulty cam or crank sensor breaking down causing it to cut spark intermittently? Or is there teeth missing on ring gear and the crank sensor not seeing the teeth so cutting the spark?

I as well as the cat mechanic have performed all of these procedures and more. As I stated before all plugs fire a few times then shut off for a few revolutions then fire again at a regular pattern. The throttle body seems to work well and the voltages and pressures all seem to be in order. He has swapped out from a running machine what seems like all pertinent parts, ie. ecu, the coil driver box, coils ect. He stated to me that the coil driver box will not send the signal to fire the coils if it does not see fuel but couldn't tell me what sensor it reads that information from.

You need to do some very basic tests instead of replacing thousands of dollars worth of parts. Test to see if it is spark, fuel, or mechanical. Take the spark plugs out and lay them on the head all hooked up to the coils. Turn the key to start and watch what happens. Are they all sparking and continue to spark? If yes, then then I would head for the throttle body. Take the air intake off and look in there and turn the key on. Do you hear it work and see it move? If not, then that may be the problem. If it's not sparking, check to see if there is voltage across the black and red wires on the coils. If not, then check the ignition 1 relay to see if it's turning on. You have to pinpoint what system the problem is in.

had a cat guy come and run his diagnosis on it and he said all the fuel pressures are right and that's when he changed the main wire harness.. he did switch the vaporizer to no avail. did not check the compression as the truck ran well before this event but will check tomorrow. pretty sure it stops sparking. when you hook up a spark detector it mirrors the way that it fires then stops. Is there an auxiliary shutdown function on the ecu? could it be a mechanical malfunction in the timing system? I did take the rocker cover off and checked that the valves were opening and closing all the way. my cat guy seems to have given up so any thoughts would be great.

Are you sure it's problem is it stops sparking? Could it be a fuel or bad compression problem?