Sounds like the control switch is bad. I think someone makes new reeds for it or find a new switch. Sound like the temp door actuator is not working along with the heat/defroster door actuator also. Default mode meaning if the system loose vacuum is hot defrost. You can check everything with a vacuum pump.
Mark, yes this is my scenario other than that the air only flows through the A/C vents, not hot defrost.
I can add that after I installed the new vacuum water valve, now the system is blowing only COLD air, even after normal operating driving distance & conditions.
Is it OK to ask on a discussion board if you have a vacuum regulator to sell perhaps? Thanks, Tommy
