(Did I cause?) Sudden shut down, no start Options

[ActionClaw]

The car: 1995 Toyota Celica ST, 1.8L 7A-FE, standard shift

I was driving down the street, slowing to a light when -- as though an OFF switch were thrown-- the car suddenly shut down. Trying to restart, it'll crank but not turn over. It seems very similar (perhaps identical) to what I experienced years earlier in the same car when I ended up having to replace the distributor. I wouldn't be surprised to learn that this may be the case again. I've read this is a common problem with certain Celicas and the replacement distributor was from bone-yard.

...BUT...I had just done some work to the car the day or so previous and had only very briefly driven it once or twice since. This may be an unrelated, coincidental but, logically, I can't help but think that there may be some (direct or indirect) connection to the work I had just completed; something I forgot to reconnect, didn't re-tighten sufficiently, etc. I've looked it over, everything seems OK (and I have no extra parts left ). Maybe one of you might catch something I'm overlooking?

What I did:
Installed new..
..valve cover
..valve cover gasket, spark plug tube seals
..spark plugs
..spark plug wires

oil change, oil filter, air filter
(spray) cleaned EGR modulator valve
(attempted to) clean the EGR valve

I've only begun to start troubleshooting and I have to double-check a few things to be absolutely certain but, offhand, the problem appears to be no spark.

What might I have done to create this condition? Any ideas?
Thanks

[Box]

I'd double check plug gap and the wires as those would be the only things you did that could contribute to the problem. Make sure everything is connected and kosher. Odds are it's the distributor again though.

[richee3]

Distributor could be at fault, or a snapped timing belt.

[mkernz22]

I'd say it would be your coil in the distributor. Don't get a used distributor, just take yours apart and replace the coil in it. That's what happened to mine, but luckily I was in a parking lot when it happened. If she's cranking, and it sounds fine, I doubt your timing belt snapped.

I feel like it would be the coil since you replaced your distributor with a used one.

[ActionClaw]

Ignition Module or ECU; how to confirm

I have a crank/no start condition due to no spark. I suspect the igniter and, after testing all ignition components I could...

- I checked all fuses I thought relevant (plus a few more I thought weren't)
- No spark at a few plug wires tested
- No spark out of distributor cap
- Rotor is turning (belt OK)
- No spark directly from coil's high voltage terminal
- Coil's primary & secondary resistance measurements were within range
secondary very low end: 9000 out of 9.0-15.7 kilohms, but within range
- Pick-up coil ("Signal Generator") resistance measurements were within range

..have narrowed it down to the "Ignition Control Module" or the ECU itself.

I've located no "official" documentation about testing this igniter; only replacing it. Many say "The ignition module can only be tested using specialized test equipment." I'd prefer not to purchase & install a new one until I've confirmed it's definitely the problem.

The only thing I found that came close was a video demonstration using a probe or test light to test the igniter output at the coil's input. When cranking, I expected to find, either..
..the test light flashing on & off if the igniter were good
..if the igniter were bad, no light at all.

Instead, I had a steady dim glow that got bright a split second before cranking stopped. Not one thing or the other, how is this to be interpreted?

The only way I know of to determine whether the ECU is good is it's self-test when turning on the car. Unfortunately, due to another problem (a short in one of the lines) the dash panel/gauges currently don't work.

My hunch is that its the ignition module but how can I logically confirm which of the two is at fault?
Is it possible to, either in circuit or removed, test an ignition module with ordinary, general purpose (not specialized) test equipment?

Also, jumping the gun here a little bit but, assuming it is the ignition module again - and from what I've read this isn't an uncommon problem- might anyone know why? Is there something else that's causing this to happen or are these ignition modules themselves faulty?

Any leads to relevant documentation, input, suggestions are all appreciated.
Thanks