Having a climate control problem...

[ford man]

The air conditioning in the '85 Ltd Crown Vic works but doesn't blow cold out of the vents ... The compressor turns on and the hoses and lines get cold under the hood but coming out of the dash there is a problem.

I've tried manually moving the vacuum dashpot in the passenger footwell in and out. I can make it get hotter but not colder. I've tried taking the 1/4 hose off of the drum behind the glovebox with the same results. My car has automatic climate control

Another perhaps unrelated problem is the air doesn't blow very hard, like highest fan speed doesn't work?...

Thanks for your help

[gadget73]

With the selector set to cold, can you feel vacuum on that clear line if you unhook it? If not, the sensor is dead. Hook up a manual vacuum pump to the can to force it to cold and see if that makes it go. If it doesn't, its probably degraded foam around the blend door thats letting hot air come past.

The vac motor in the footwell is the fresh air / recirc air door. It won't have anything to do with temperature regulation.

Pull the fan out and clean it and the inside of the housing. Try and hose off the evaporator too. Its probably packed up with lint and dust and crap.


Where is it you live that air conditioning in January matters? It hasn't been above freezing here in a couple weeks. I'd be happy to have an excuse to work on air conditioning rather than avoiding large areas of the property due to lack of interest in freezing my bits off.

[ford man]

Very helpful! I hooked up a vacuum pump to the can behind the glove box and with 20 vacuum it seemed to make a meaningful difference in the cold temperature coming out of the vents. Do have to replace the sensor about the glovebox under the dash pad again? Is there a way to hook it up manually with out a sensor imput?

How do you pull the fan out? Is it a bitch to get to? It still barely blows out the vents...you think it's because its really dirty?

I'm in Los Angeles... it was around a high of 79 today.

[gadget73]

If the sensor isn't passing vacuum, it may well be dead. It would be worth making sure that it has proper vacuum to the input side of it. If its got full suck on the vacuum side and no suck on the output side, your sensor sucks. No real way to bypass it either. Unhooking it makes it full hot. Bypassing it makes it full cold. If you want anything in between that, you need it. I guess you could install a solenoid with an on/off switch or figure a way to control a variable vacuum regulator somehow. Regulators do exist, and you could probably replace the stock system with a customized digital controller that would take over all of the climate control functions but thats not a task for the faint of heart or those not well versed in digital circuit design. I am not, but I can make the stock nonsense work within it's wonky design limitations.


Fan is under the hood. 4 bolts, not a big deal to remove. Worth making sure that its not packed up with crap. its probably the easiest possible solution. The other one basically involves tearing all of the ductwork out to rebuild the air doors. The blower is like 15 minutes to pull, the plenum assembly is a couple hours.

[turbo2256b]

The whole countrys got a climate control issue it must be the vacuum motor controling the jet stream.

[ford man]

If the sensor isn't passing vacuum, it may well be dead. It would be worth making sure that it has proper vacuum to the input side of it. If its got full suck on the vacuum side and no suck on the output side, your sensor sucks. No real way to bypass it either. Unhooking it makes it full hot. Bypassing it makes it full cold. If you want anything in between that, you need it. I guess you could install a solenoid with an on/off switch or figure a way to control a variable vacuum regulator somehow. Regulators do exist, and you could probably replace the stock system with a customized digital controller that would take over all of the climate control functions but thats not a task for the faint of heart or those not well versed in digital circuit design. I am not, but I can make the stock nonsense work within it's wonky design limitations.


Fan is under the hood. 4 bolts, not a big deal to remove. Worth making sure that its not packed up with crap. its probably the easiest possible solution. The other one basically involves tearing all of the ductwork out to rebuild the air doors. The blower is like 15 minutes to pull, the plenum assembly is a couple hours.

Ok thanks I'll check all of that

[sly]

The whole countrys got a climate control issue it must be the vacuum motor controling the jet stream.