1996 Mercury Grand Marquis Heater Control Valve?

The air is cold when the heater is turned on. Plenty of antifreeze in the system. A/C works fine. The car has the electronic HVAC system. So I went out and purchased a heater control valve for the car. Problem is that I can't find it in the vehicle. I know at one point they were eliminated but the parts book did list an application for mine. So does anyone know where this thing is located?


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Find where the heater hoses enters/leaves the firewall and trace it towards the front until you bump into it.

IIRC as you face the engine compartment from in front of the car, the right heater hose connects to the back of the intake, the left hose snakes downward and I believe it's the one w/the control valve on it.

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Great picture! This thing is really deep, huh?

That's what I'm thinking! I had a '95 Marquis for a long time, traded it in during the cash for clunkers deal. Never had occasion to work on the heater valve. Actually, nothing much went wrong w/it, period. Very reliable, ran decent considering it only had the 4.6 2V. Cushy ride, easy chair comfort. But BORING! Now, if it had a Mustang GT engine in it...

I just went outside and took a look. Its getting dark now. So I had really bad light even with the flashlight. I'll look again tommorow. Your right, it is a good car. Not much really goes wrong. I have 154K on mine.

Should look something like this.



Cole

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I have the new one here. So I know what it looks like. Alldatadiy.com doesn't even show it. This really sucks.

Will this help ? http://www.2carpros.com/questions/l...l-blower-lockou




Cole

I gotta go out and look again. But that is the valve without a doubt! Thank you!

Might need to get under it or go through the wheel well opening to get at it. I hope not for your sake.

I get the feeling that this thing is located under the intake manifold. Ford placed a heater hose underneath it that's real hard to see. This is probably one of the stupidest things I've ever seen in a car done by the factory. Where do they get theses guys from?

I just looked at autozones web site and the thing is practically under the manifold. But the installation instructions they give make it appear that u can change it without taking the manifold off. i'm going to take a good look at all of this when the sun is up. thanks for all the help guys!

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

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