Chrysler Repair: 3.3l fwd no start, one coil pulsed, snap on mt2500, camshaft sensor

Question
Hi, 1991 Plymouth voyager 3.3l

became a no start, after breaking l.f. axle, though I am convinced this is not the cause.
Has power from asd relay, and the E.C.M. is pulsing the ground side of coil#1 only. Also using atm test function of Snap On mt2500, only one third of the coil has spark for about 45 seconds. Then nothing.  Am I missing something small, and Important? E.C.M. has been replaced with a known good componant. compression is 100-132 across all 6. fuel pressure is in spec. Why is only one third of the coil being pulsed?

Answer
Hi Chris,
The problem may either be in the wiring from the ECM to the coil or it could be the camshaft sensor is not working well and is only picking up the signal from one of the three slot pairs on the camshaft sproket. You could verify that the wires from the three coil driver wires are patent with an ohmmeter. The relevant pins on the 60-way plug are 17, 18, and 19. If you hold the plug with the short tab up and the pins facing you, start counting from the left of the top row as #1. The dark blue/yellow at the coil goes to 17, the red/yellow goes to 18, and black/gray goes to 19.
But I would more suspect the camshaft sensor which is responsible for calling out which coil to fire. It may even have been recognized by the on-board fault code recording capability of the ECM. You can read out the memory of the ECM yourself to see if you get a code 11 (crank sensor problem) or a code 54 (camshaft sensor problem). Begin a readout as follows: Take your ignition key and turn the ignition switch "on-off-on-off-on" and leave it "on". Do this switching quickly so that no more than 5 seconds elapses. Then watch the 'check engine' light to begin to flash, pause, flash, pause, etc. Count the number of flashes before each pause and make a note of them in the order that they come. The last two flash groups will be 5 in each. Repeat the readout until you have the numbers accurately (the same result, two times in a row). Then pair the numbers two at a time in the order they came, to form two-digit numbers, for example the last number will be 55 which is the code for "end of readout".
Let me know if either of these approaches bears fruit. I am sure one or the other would explain only 1/3 of the coil being energized.
Roland