electronic ign. questions (archive)

I've got an ignition problem on '80 320i (electronic ignition). Usually there's no spark at all at the plugs, Occasionally there's a weak spark.
Have replaced plugs, plug wires, dist. cap and rotor.
In my most recent tests, there wasn't even spark at the coil wire, so I'm suspecting the "pulse generator" in the distributor. I tried to test it last night with a digital voltmeter.
In Chilton's manual, they say you should get 50 mV voltage between terminals 7 and 31b at the plug into the control unit, when cranking the engine.
Uh-oh, my plug at control unit is not numbered anywhere.
So tried to track down which terminals they were, by looking for continuity betw. distrib. output plug and control unit.
The brown wire from dist. was no problem, (actually it had continuity w/ 2 terminals at control unit plug) but the green wire from dist. didn't have good continuity w/ any of the terminals at control unit plug, (but had weak continuity w/ the same 2 terminals as the brown wire, above).

So OK, I just tried checking for voltage directly at the 2 output pins on the distributor itself. The voltage fluctuates widely and inconsistently between, say, -70mM and +60, with plenty of readings in between as well (on a digital multimeter). There's no stable reading, and no clear repeating pattern either.

So now, can anyone out there tell me what's going on?
Does that mean the pulse generator is good or bad? Anybody know how the numbering in the Chilton's book corresponds to the actual plug on the car?

Thanks-

Ron

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