1986 Country Squire wagon. Replaced heater core in the fall. The car will not switch from heat or cold. No matter where the temperature is set it still blows out cold air. This ties into the next problem. Under a load of 5 or more seconds the car looses all vacuum and the vents default to the defrost and then hot air will come out. Once the car regains vacuum it is back to cold air and vents. When I had the heater box out i cleaned out all of the mouse piss and nest and everything looked alright. Any ideas? I have been getting heat all winter by removing the vacuum line on the top of the box behind the glovebox.
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Since it loses vac so fast, you've got a pretty major leak. The usual suspects are the soup can under the hood and the thermal blower lockout, as well as the check valve at the vacuum tree.
If all of that is good, it must be in the car somewhere. Since its at full cold, basically that means the interior temperature sensor is bad. Unfortunately these are no longer available and we haven't figured out a proper solution to this. I've had one apart, and honestly there isn't much to fail in there. Its basically a needle in a seat, plus a temperature-sensitive spring. I suspect it fails when you get a dust booger on the needle and it no longer seals. Might be able to flush through the ports with some electronics cleaner and make it go again, I honestly don't know. I've also wondered if dunking one in an ultrasonic cleaner would help.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers -
Sounds good I will start looking for leaks I appreciate the info I was wondering if there were any locations where they commonly leak.
As for the temperature sensor...Is that the blue doo-hick (technical term) underneath the dash pad on the passenger side of the car? if so I have had that apart and nothing seemed wrong. Cleaned anyways. What I was wondering is there a way to mechanically connect the temperature control lever directly to the door in the HVAC box that controls the heat and cold? I have no desire to use the auto-climate control anyways.Comment
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yep, thats the one.
You'd need parts from a non-auto climate control car. The cable from the control head to the blend door, and whatever bracket is down there. The vac can would have to go away too.
You're using the auto whether you want to or not. Its never manually temperature controlled, the only thing you can manually control is the fan speed.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousersComment
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Check valve is Motorcraft YG-337.
I've replaced this thing enough to know it off the top of my head now.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
Originally posted by gadget73
... and it should all work like magic and unicorns and stuff.
Originally posted by dmccaig
Overhead, some poor bastards are flying in airplanes.Comment
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