I have this anoying problem with my 97. When I accelerate the air flow changes from the vent to the floor. The dash control does not change. I assume it is vacuum related. I disconected a vacuum line near the relays that are mounted in the engine compartment. This defaulted to the floor. I don't know what that told me, besides it being vacuum related.
I have changed most of the vacuum hoses and fitting on the engine. But not all of them. I just found a tank
under the front right fender that might have a loose fitting.
Any thoughts would be apprecitated.
p.*. I suffer from the chugging and surgging problem, and have apprecitated the discussion on how to resolve this problem.