69 C10 Idles Rough. Stalls.

[jdot]

I bought a 69 C10 a month ago. It was running great initially, but the last few weeks it's been idling rough and weak, and stalled a few times at stops. It would run great at the beginning of the day, but 6 hours later when I would start the truck I would notice the issue; seemed more pronounced when the truck had run some for the day or the engine was warmed up.

No issues starting. Even the few times it stalled, it started right back up.

The last week it seems to be getting worse. The rough / weak idle is present right away now on the first start up of the day. When I put it in Drive (automatic transmission) it feels even weaker until I give it some gas.

One last detail: when it gets weak the fuel gauge needle seems to die also, almost as if the power is going, but the other gauges not affected. Turning on the headlights does not make it idle any worse than it was.

Are there any known issues for this model that could be the cause? Or, any ideas on where I should start?

[geezer#99]

You need to start with more info!
What motor?
What Carb?
What distributor?
Do you have a lumpy cam?
Do you have headers?
What's your initial timing?
Have you checked your timing lately?

[jdot]

It's a 350 4bbl. It looks like the stock headers. I'm not sure on the distributor or cam, and I have not checked the timing.

[geezer#99]

You need to check the timing.
At your mile high elevation you need way more initial timing than normal.
Be sure to plug the vac line to the vac pot when you check it.