My truck has been acting up again lately. It did this intermittent thing a few months back where it would start and fast idle fine but within 2-3 minutes, it would slow down, almost like it's flooding, and the exhaust smelled real rich. So I'd stand on the gas and a plume of blue smoke would come out and float down through the yard.

Well, the problem is back again. Every morning though. And I'm able to pull out and drive it, but when I come to a stop and push the clutch in, it idles real slow. It's about a 10 minute drive to work for me, and when I get there it still does it.

I've tried a few things. Sometimes if I let it sit for 10 minutes and start it again, it will idle perfect. Most of the time. Yesterday it did so I shut it off real quick and checked the distributor and the coil real quick. The coil harness had some corrosion on the + and - connection so I cleaned it up with some fine sand paper.

Next I checked the distributor cap and noticed the number 6 post was sitting a little bit higher and the flat part inside the cap is pointing outward, away from the rotor. Like it was jammed in there wrong. I started to twist it but realized it would probably come loose.

So I started my truck again and it idled fine. Thought I had it narrowed down to one of those until this morning when it started acting up again within 3 minutes. Is it the coil getting warm causing the spark to lose its charge? Any other suggestions? Carb?

351m. Rebuild 2bbl 2150 about 5000 miles ago.