Reply to "Engine Cutting Out"

I was finally able to get back to this today and here's what I found:

I was going to do John's MSD jumper test when I noticed one of the wires for the ballast resistor was hanging off and just barely making contact. I pushed it back on and it was very easy to slide back off, but I tried to start the engine anyway and it fired right up! I turned it off and on several times and let it idle a bit. Before the engine got too hot, I slid the loose connector back off (it was a crimped on female), and used a pliers to sqeeze the prongs down a little tighter. It was nice and tight going back on, but I noticed the blade coming from the resistor was wobbly.

I tried to start the engine again and it just cranked. I took a plug wire off and had no spark. I removed the connector again and slid it back on, but not as deep. The engine started back up and idled just fine. I wobbled the blade with the connector on it while the engine was running and it did not cut out, or even stumble.

I took it for a test drive, and the car hesitated a few times, like it wanted to shut off, but caught itself. After about 15 minutes, I shut the engine off, and it would not restart, it just cranked. After a while it started and shut off, then started and ran. I headed for home, but had to stop for gas. The engine started right back up, but cut out before I got to the street. This last time it started, and stayed running all the way home, but stumbled many times.

Am I right in guessing that the wobbly ballast resistor blade is giving me inconsistent contact internally? I don't see what else it could be, as the loose resistor connection solved my 'no start' problem.

It looks like an MSD type of resistor (.8 ohms). I have an MSD 6AL, with a stock coil, and a Mallory Unilite pickup in the Motorcraft vacuum advance distributor. Should I be using the Mallory type of ballast resistor (.75 - 1.5 ohms), or does it not matter?

Michael