1996 Mercury Grand Marquis Heater Control Valve?

Originally Posted by latech

That is not a valve, it is the ambient temp sensor for the HVAC auto system. There isnt a valve on this car. It has a blend door and probably has a stuck blend door motor/actuator.
If you open the glove box and pull it out, look over the top of the heater box towards the dash center, the actuator is there. With the key on and the temp turned to hot, beat on it or tap on it with a little hammer, try moving the temp knob when you are doing this then turn it to hot. Chances are you will get it moving again. LA Tech
Oh and there is nothing under the intake but the hose.If you ever replace it use a high quality high silicone hose and re use the constant tension clamp....yes that is what they are called.Gear drive clamps will allways need to be retightened after an install, constant tension is just what it says, constant tension.They are far better clamps, as the hose softens it just keeps tightening all by itself, no need to remove the intake to retighten

Originally Posted by latech

That is not a valve, it is the ambient temp sensor for the HVAC auto system. There isnt a valve on this car. It has a blend door and probably has a stuck blend door motor/actuator.
If you open the glove box and pull it out, look over the top of the heater box towards the dash center, the actuator is there. With the key on and the temp turned to hot, beat on it or tap on it with a little hammer, try moving the temp knob when you are doing this then turn it to hot. Chances are you will get it moving again. LA Tech
Oh and there is nothing under the intake but the hose.If you ever replace it use a high quality high silicone hose and re use the constant tension clamp....yes that is what they are called.Gear drive clamps will allways need to be retightened after an install, constant tension is just what it says, constant tension.They are far better clamps, as the hose softens it just keeps tightening all by itself, no need to remove the intake to retighten

Originally Posted by dstones

Hi Coodeville,

I'm having the same issue with my 1995 Marquis. Did you get to replace the heater control valve? And if so, did it work out for you?

I'm hoping its not the unit on the dash side, the manual is calling it a heater and AC control assembly..


Thanks!
dstones