1984 Ram Crank No Start

Like Mattax said.

Just to add.
The 5-pin ECU used to require it's own power supply with an External Ballast resistor.
The 4-pin ECU, has the power-supply inside the case, so it no longer requires it's own ballast .
The 4-pin ECU, will run just fine using 5-pin wiring. The extra power-supply is just dead-headed in the socket.
But your truck shouldn't have 5-pin wiring, so this information is just information.

If you even once saw a stream of sparks, no matter how you got it, then EVERYTHING at that moment was working, in whatever position your key was in.
If you see the one-spark discharge when the key is turned from run to off, then both the coil and the ECU are working and the only questionable piece is the Pick-up, unless the distributor driveshaft has quit turning, or the reluctor gap is waaaay off spec..
The Reluctor gap spec is .008>.011 IIRC, but in my experience, the pick-up will signal just fine anywhere from zero gap to .030.
If the timing chain has ripped all the teeth off the nylon upper sprocket, then distributor driveshaft will stop spinning. But the engine will crank funny with out compression at the right time, and usually the pistons will bend some valves.
If the timing chain has only jumped some teeth, the driveshaft will still turn, the ignition will still fire, but at the wrong time, and the engine will not start. The timing chain, when it jumps, it almost always happens whilst cranking a cold engine.
Put the engine at TDC/compression of #1 cylinder. as close as you can figure out, close is good enough. trace the #1 wire from the plug back to the cap. Mark on the distributor body, the position of the center of whatever tower that wire terminates at. Pop the cap off, and make sure the rotor is pointing to that mark you made, within a few degrees.


OOps , I was typing while Mattax was already posting,
Sorry man,