1989 323/Tracer won't start
 

Possibly the electrical portion of the ignition switch if no power to the coil. Did you check the fuel pressure? The tube from the MAF to throttlebody has to have a perfect seal due to a fuel pump shutoff inside the MAF. Did it die while driving and not restart or has it been sitting a long time?

Try a boost start, and with the boost car still connected, see what your spark looks like then. A weak spark with the plug out (atmospheric pressure) is no assurance of any spark at all in a cylinder on a 120 psi. compression stroke. A weak battery, poor battery and coil connections, poor chassis or engine block ground, a defective ignition capacitor, and a worn out HT ignition harness should be considered too.
But first, get the critter running, unship the booster cables and check that the volts from battery +ve to chassis are above 14 Volts at fast idle, (i.e. the alternator's healthy). If the car's primary electrics aren't up to par, don't expect the ignition system to be any good either.

Still isn't starting, here's what I tried:

Well hixx was right about the MAF tube connection to the throttlebody - it was in fact loose. I'd neglected to tighten it back down after disconnecting the tube assembly to get to the thermostat. (I removed the thermostat as part of a thorough backflush.)

Unfortunately, after making sure the MAF tube sections were again secure, it still didn't want to start... I then attempted oldeng's suggestion of a jump with another vehicle, several times, but no joy.

To answer hixx's other questions: it didn't die while driving, and it hasn't been sitting a long time. The last thing I did on it was remove the thermostat, and immediately after doing so, it refused to start. I've had the thermostat out before, and it's always started of course - as it should. It hasn't been running well due to an overheating issue, but throughout my work on that (like replacing the water pump), it's always started.

Much thanks to both of you for your help so far. Any suggestions on what I should try next? Is there any way I can bypass the ignition in order to rule that out? Elsewhere on the Web, others who've had starting problems with this engine were able to solve it by replacing the entire distributor. But I don't have a spare coil or distributor for a swap-test, and I'd like to think there's a smarter way to rule them out...

What did the spark look like when the car was being cranked with the boost start? If fat and healthy, that should clear up the coil/ distributor ignition issues.
And what about that fuel on the plugs; with an earlier overheating history it makes me suspicious; are you absolutely sure that's fuel and not water?

I recently replaced the distributor, being careful to install the new one in the same position, but it still wouldn't start. As a test, I rotated the new distributor clockwise and found a spot where it *would* start. Except it ended up being 1/4-3/8" difference compared to where the old distributor was, and since I'm a noob, I don't know if that's a lot. I'm wondering if it can be assumed that the timing marks are no longer lined up on the camshaft and/or timing pullies? And if I take the timing cover off and everything *is* in alignment, then what does that mean?

I should mention that not too long before the no-start issue appeared, I'd taken the timing belt off during a water pump replacement. I reinstalled the old belt instead of putting a new one on because it seemed to be in excellent condition. It was still starting after I had everything back together, so I didn't suspect a timing issue at first. But now I don't know what else it could be.

Sorry if these are stupid questions - I just want to verify that I'm on the right path before I dig back in to it since getting to the pullies is a pain in the a**.

You can reuse a timing belt provided you don't get grease on it and you install it in the same direction of rotation.

You need to get a timing light. A timing light is the only real way you can set the timing by rotating the distributor to the correct position. If the distributor is really rotated to a spot that doesn't look right you might be off by a tooth. The marks on the camshaft gear are very crude and hard to see.