I've encountered a frustrating warm idle problem on my `71, and I'm
interested in any avenues of investigation that people care to suggest.

Problem is that the choke must be pretty much closed to keep the engine
running, even when warm. Normal logic says carb problems or vacuum leak, but...

I checked the intake manifold and associated vacuum lines coming off of the
manifold- no leaks.

I tried a second (used) carb, and there was no difference in the problem.

Idle cutoff solenoid is getting juice.

Spark looks good and strong.

Valves in specification.

New plugs.

Plenty of fuel in the bowl.

Let me know if you've seen this one before.

-David Saffren