Hello! I'm Rixster...
I am going to see if I can help you out on this but I'm going to need to pick YOUR brain a bit first...
Is this vehicle Carbureted with a 4bbl. Rochester Quadrajet?
Does this vehicle sit often?
I'd be willing to lay a wager that your accelerator pump plunger in your carb. is faulty.
Which would entail an overhaul.
To check this...
Remove the air cleaner lid and shine a flashlight down the primary side of the carb. under the choke flap. (you may have to hold the choke flap open) Apply the throttle gently but firmly and watch where the fuel squirts out of the accelerator nozzles. It should come out readily in a fairly strong stream strait toward the venturis. If it does not or if it is just a "dribble" type squirt. Then you have confirmed the need for an overhaul.
I recommend overhauling the carburetor as opposed to purchasing a remanufactured one. Just because I've had better luck that way. (I may be biased a bit because I've overhauled and modified hunderds of these sucessfully)
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