13. The air valve dashpot and its linkage adjustment is just as critical to the secondary operation of the TQ as the air valve spring tension. The diaphragm link acts as a stop on the air valve shaft, holding the air valve shut while there is vacuum applied to the diaphragm. Stab the throttle and manifold vacuum drops off almost instantly, but the diaphragm has an air metering orifice, controlling the rate at which the diaphragm bleeds down and lets go of the air valve. Make sure the dashpot isn’t blown out, and take the time to adjust all the carb’s external linkage to specs.