I have a quadrajet #17085213.i was cruising down the highway at 55-65, it slowly lost its power and began to decelerate no matter how much throttle I gave. it will only cruise at 35ish with the vacume at 5inches, and 14 inches at idle. Normally I have 17ish inches at idle and cruise at 55-65 with 10 inches of vac. It's difficult to get it to accelerate at all, but if I go to the floor and open the secondaries it will accelerate like normal secondaries with 0 vac of course. I have vac advance connected to manifold vac, the port on the bottom left corner if your looking into the hood. I'm driving a 86 chevy g30 hi cube. 5.7L 350. M in the VIN. I think it's a carb thing but could it be just a vacume leak somewhere else on the engine.
