Simple test. With the motor cold, pull the breather off and see if the choke is open, or closed. It should be open. Pull the throttle linkage back, and the choke should close. "spring tension". get someone to start the car, and watch the butterfly valve. If it fires, then stalls, and the valve doesn't open, it's your choke pull-off, or the vacumn line to it..
Let us know what you find.