Well, here's one I've not been able to figure out...
Problem: Overnight-cold engine, when started, misses sporadically. While testing spark w/timing light, noticed that when it was missing, the timing light followed suit. New cap, rotor, plugs, wires, 3 different ignition modules failed to clear problem. Retested using timing light and found that same results acheived by connecting trigger lead to power supply of coil, which meant the coil wasn't being triggered correctly. Since 3 ignition modules acted the same, that pretty much ruled them out.
That left the hall effect switch. Pulled the distributor off the engine and took a peek. Light film of oil, so internal seal is going/gone.
What really got my attention though is the plastic ring which holds down the wires going from the connector on the edge of the distro base to the hall switch... it was mostly gone, and what little was left was melted and dripping down!
Engine hasn't shown any signs of overheating. Any idea what might have caused this?
Thanks! Tony