Good stuff. You know your stuff because all you've said matches what I have learned!
At this point we have replaced both reference and speed sensors, procured an alignment dowel, gotten decent purchase with pivot bolt despite broken area and set gap.
Engine sounds exactly the same, cranks, squirts gas (noid light confirms injector pulses, plugs are wet)
Have about 38psi fuel pressure at the rail.
Have spark but it doesn't look bright and blue so I pulled the cap, looks fine, rotor looks fine (it only fits the cam shaft one way with a set bolt so can't really get that wrong) confirmed wires are correct as to firing order, then I pulled the coil wire off the dizzy and the terminal inside the wire looked quite roached, corrosion and bits missing.
Went to pull it off the coil and it fought HARD. I won but the wire pulled right off its end, it stayed in the coil then the bit sticking out broke in two.
Made temporary coil wire out of old Fiat plug wire.
Checked coil for resistance, primary winding is .9v should be .4-.6
Secondary was infinite, cleaned the terminal and can occasionally get the probe to tell me 5000ohms which is in spec but hard to get.
Ordered new coil.
I also pulled the DME computer, took it apart and checked solder, all looks spectacular.
I've found the DME harness pin out and am going to attack with multimeter (just like I did to my X 6 years ago).
PO has left a mess of wires and it could be a ground is missing or something and the DME is confused, or the wiring to the sensors is bad.
To my mind something is confusing the DME and it doesn't know when to send spark so it's just guessing wildly.
I should post a video of it cranking. It turns over nice but it "thumps" and "knocks". Due to badly timed spark I would think but I don't know.
I need to recheck compression too. Even if there's a major issue with a cylinder or two, it should still fire on at least one. My X did.
I'll start in on wiring check while waiting for coil to arrive.
I'm not very confident it was "weak" spark holding up the works but possible I guess.
I can tell by the wrong bolt that was holding down the speed sensor, and the broken block, and the missing alignment dowel and the completely disintegrated connectors that some PO had messed with the sensors. That is now all cleaned up. The sensors themselves were never changed, judging by the fact the connectors were extremely brittle (old heat cycled) and were both unbelievably seized up in the bracket. It took hours to get them out. The speed sensor had to be drilled out and slowly chipped out of the bracket's bore. Unbelievealbe. They are supposedly slip fit and "should" be able to be pulled out with relative ease, most seem to cement themselves in there. New ones have lots of anti sieze on them.
There was also a lot of talk of alarms messing things up but I don't think the 924 had 'em.
Holy crap, I just found this image:
If this is correct. PO had wires wrong as I have #1 at 1 O'clock...........interesting
If this is true, and my memory is good (ya, right). Wires are WRONG. I blindly followed the PO on this, I should know better.
Will test this theory at 3:35p.m. EST 5/16/16.......stay tuned, oh the drama.........