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this model had an electrical solenoid for the idle circuit. when the solenoid did not function, it will only run on fast idle when the main jet operates and the choke is on. after it warms and the choke comes off, the car will die. this is the heart of your problem. First, check all your fuses. a blown ignition fuse will cause the solenoid to be inop. Also check your charge system. this old of a car could have a bad alternator and will not supply voltage for the solenoid circuit. There are not too many carb guys out there anymore(i'm older than dirt and been around-HA!) Good Luck---Sparkbolt

Romney might have it- grab the whole carb and see if it is tight to the manifold. Had an 84 that wouldn't adjust and laid my hand on it and the whole thing was loose- tightened it up and all was well- It also has some hidden vac lines off the back you can't see.

With that age many things could be wrong, I say get it to a good shop for a diagnosis first then figure out if you want to save money by doing the work yourself.

Diagnose once = repair once

Guess = guess again

you have a vacuum leak or something internal in the carburetor is sticking. the hopping up and down means air is getting in where it shouldn't be.