Had a couple issues that caused me to remove intake plenum down to fuel rail - swapped plugs & wires while i was in there. Reassembled, cranked & ran fine. But I had a gas odor. Found bad leak at #2 injector (blown O-ring).
Disassembled down to fuel rail again, replaced o-rings, reassembled. Now - no start. Tried for half an hour - hit with ether a dozen times - not even a hiccup.
Did spark test with old plug - no spark visible.
Checked power to coil pack - has 12.6V when key is on.
No blown fuses inside or out
Replaced coil pack (even though existing one is <1 year old) -still no spark
At thispoint i'm asking myself....
- What could i have broken during remove/replace of intake plenum?
- what failures would trigger this situation and how do i get past them?

 

I think the test for the 4-wire connector (the one which goes into the coil pack) has one hot wire and three routes to ground.
Red lead into first wire (seem to recall purple wire on later Rangers) and the black lead into one of the three holes...cranking the engine will give you flashing
I guess use a test light or watch for jumping numbers on a digital meter.

Won't a bad/unplugged Crank Shaft Positioning Sensor result in a no spark condition?

 

Check your crankshaft sensor. These sensors rarely go bad but anything is possible. It could be cracked. Your 97 should use T-Series PC14T if needed.

Did you happen to unplug the or mess with the cam shaft position sensor while working on your truck? The ECM uses the signal the CPS sends to fire the spark plugs and inject fuel. If it's "boogered" up in any way it will not start