1996 Mercury Grand Marquis Q&A

1996 Mercury Grand Marquis Question: 1996 Grande Marquis V8 The heater is always on even when you turn on AC

A few months ago the system started to make a poping noise inside the dash like one of the control functions was in a stuck position. Noise stopped now AC will not work. -
Answer 1
Probably a blend door actuator has failed. When they go bad....the vent will not switch from the heat to a/c....Different HVAC lines. Need to have inspection done to see if this is the cause but I suspect it is. -