Still trying to get my son's '89 wagon running...

With a good spark plug stuck into the spark plug wire and grounded against the exhaust manifold, on all four there is a very irregular spark. I'm assuming it should be regular, tested this way.

The original owners replaced the timing belt, and did who knows what else. They said it ran before, but not after, the timing belt job. It tries to run, but never quite catches more than one cylinder at a time. It also sort of chugs hard every once in awhile when cranking the engine -- like the rotation stops completely or runs into something... (I'm not a real mechanic, ya know)

There is nothing in or on the distributor other than the dust shield and the rotor. No vacuum diaphragm, no wires, nothing that looks anything like the impulse sender and all that in the diagrams in the books.

My '83 runs, but it doesn't have a vacuum diaphragm on it, either. It does have a plug with wires clipped into the side of the distributor, and impulse-sender-looking things under the rotor.

Are the distributors the same on the '83 and '89?