Ignition.....

[69 Post Sedan]

I’ve been having issues with my Chevelle lately as it won’t stay running at idle and spit/ sputters at higher rpm. I’ve changed everything in the ignition, it’s all new, distributor, coil, wires, plugs, etc... I’m currently running a Mallory Unilite mechanical distributor and coil, that’s it. Nothing fancy.

I noticed tonight that when I have the timing light on it, the light/strobe will stop flashing and then it will die shortly after that unless I rev it up to keep it running. If I keep the timing advance, a lot, it doesn’t seem to do it but as soon as I get it lower than 20* advance, it won’t stay idling.

It seems that when I rev the motor up, the timing retards for a second, then advances......?

There is a back story, one time when I was working on it, I started the car up and it ran fine but it started to smoke between the brake booster and the firewall. I accidentally forgot to hook up a ground wire to the ignition and a wire, not sure what it went to, got hot and was grounding out on the brake booster bracket. This always a couple years ago......I’m not sure if that has anything to do with the issue I’m having now or not.

Any thoughts on what might be the problem or how to diagnose it? I hate to keep buying parts if it’s not justified but I’m thinking of replacing the engine wire harness.......I’m not very good with electrical on a car but in so have a friend who is. I’m thinking we/he needs to check voltage on everything to see it there’s an issue.

Thanks in advance, Kurt