First make sure the butterflies are off the fast idle cam. Then make sure the timing is per factory decal, and that TDC on the damper is in fact TDC on the piston location, that there are no vacuum leaks, that the PCV is in good shape and properly plumbed, and that the distributor vacuum advance is properly routed to the sparkport..
What I'm suggesting is that if the butterflies are not in the correct location, then the mixture screws will not respond properly.
But if the butterflies are in the correct location, then, I have one more tip.
Remove the mixture screws,one atta time, and blow compressed air into the passages; fuel should shoot out the top of the carb, so throw a rag over the airhorn. This is your proof that the passage is clear. You don't need 120 psi for this so don't try to inflate the carb;just a short little couple of blips from a low-volume nozzle. Reinstall the screws lightly seated and back them out 2 turns and see what happens. Many times this situation occurs when dirt gets stuck in the top of the airbleeds, or gunk in the emulsion tubes. So if this doesn't cure it, or if the situation returns, then for sure
what they said.
If you get lost, check your T-port sync.(see below)
If the choke won't stay off, you have other issues that must be solved, preferably first.
After you get your T-port synced, you can diddle the distributor, but you must limit the power timing to eliminate detonation. I am not familiar with California cars,controls, or regulations, so if you get into trouble,it wasn't me,lol.
