I installed a new electronic distributors.(mallory). Port motor had a miss, two cylinders were firing intermittenly. Changed plugs and wires, no help. Swapped distibutor to starboard and the problem is there now. I could remove the #1 and #6 plug wires and rpm doesnt drop. I put the old points distributor in and same thing. I get a good blue spark at the plug end of the wire and from the cap as it jumps to my test light. The only thing that I can think of it being a problem with the cap. Thats the only thing I havent swapped. It is a new cap that came with the new distributor. Could a cap cause this? There is no moisture in it and no signs of carbon tracking. Plugs are all new and so are the wires. I alos swapped coils with no help. WTF, this is driving me nuts

When I put the timing light on #1 it flashes erratic and kind of slow, but if i put it on #2 wire it flashes very steady and fast.

Yes it could be the cap try swapping it with the othe motor

What ever happened with this problem? I am having something similar with basically the same engines except thunderbolt IV distributor / ign.

Bad cap.

Could be a bad rotor too......