What could cause the secondary venturies not to want to open?

 

1) Choke not opening all the way, and not releasing the secondary interlock linkage cam.
2) Stuck linkage
3) 1 & 2

 

Ok, I'll check that out. It is running seriously rich and running like crap from 2500 on up. It has a slight hesitation of the bottom, but I haven't driven it in around 10 years. Is there an easy way to id if the choke isn't opening all the way up?

 

Based on that then, my answer is #1.
Remove air cleaner, look at choke butterfly, butterfly should be straight up & down with a hot engine. If you don't know how to adjust the choke and linkages, google "Quadrajet choke adjustment". I know there's a ton of info out there, and pictures will help a lot.

 

The choke appears to be open all the way. It reads around 90 degree from the carb body. But I noticed the vacuum breaker (I believe thats its name) shuts when the car is running and is open when its off. I can hold the secondaries open and move the linkage and but it still wants to shut. I am going out on a limb and beginning to think the vacuum breaker is bad. I can't see any way of fixing it...just replacing it. On a positive note, when the venturies are open and the throttle is opened up it sounds a lot better (cleaner, and more powerfull)