My vent is stuck on defrost. Over the last couple of days while i was driving the A/C would switch off of vent and it would go to defrost for like 30 secs, then go back to A/C on the vents. Today its just stuck on defrost. I'm guessing this is some kind of vacuum line problem? HELP ITS HOT.
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sounds like you've probably in the need of that check valve on the firewall with one out to the vacuum tree and two in from the firewall. (That is if it's the same as most other cars I've seen)
You may also have actuator issues for the vents (these actuators are usually behind the control panel in panthers). I'd bet on the check valve (and it's cheap to replace).
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. -
Vacuum leak. check the soup can and the lines to it.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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Even if one vacuum line fails, it's enough to cause running problems. Just out of curiousity, what shape are the head-gaskets and seals in the engine? My step-bro recently had these parts replaced and vacuum was restored. Do the head-light doors stay open after use? If so, a vacuum leak is imminent around the soup cans, vent valves, etc...If they stay down, the leak is focused within the vent system inside the dash. The diaphram may also be dry-rotted and won't be able to move the vents.'79 Continental Town Car
'90 Crown Victoria LTD
'94 Crown VictoriaComment
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I haven't had much trouble with the in-dash crap. Every time I've run into the hot defrost issue its been under the hood, either with the soup can or the TBL switch.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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I'll have to check the head-gaskets. The headlight doors work fine though. The car has had running issues on start up, kinda like a bad misfire where it will shake and buck for a few minutes and stall if i drop it to gear and turn the wheel. Thats only sometimes though, very rare, and only until it warms up. I figured that was a carb issue.Originally posted by 79lincolnlover View PostComment
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every time I've had issues with the defrost thing it's been that check valve on the firewall allowing the vacuum from the soup can to be bled off during low vacuum running.
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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Its almost guaranteed that its not the head gaskets. You have vacuum leaks. A 302 doesn't blow head gaskets unless you majorly overheat it. Vac leaks cause running issues with carbs as well as EFI.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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I have a 351, but i guess its basically the same though. What about how it was switching from defrost to vent on its own?Originally posted by gadget73 View PostComment
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same story... generally a vacuum leak in the A/C side of the vacuum lines (or the soup can). check the check valve though. If it's leaking it will do the same stuff.
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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351's are even less likely to blow head gaskets than a 302.
The climate control system defaults to hot defrost with a loss of vacuum. Its a safety feature. Any leak causes exactly what you describe. Its classic ATC retardedness.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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Thank you much, I got a lor of car work to do today, hopefully I'll get around to it. I'm replacin the rotors and brakes on my moms honda and doin some body work on my friends Mitsubishi, then I have to remove my door panel to fix my door handle which doesnt work.Originally posted by gadget73 View PostComment
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ok so I had the problem diagnosed Friday, they say its the valve solenoid. They said they had the part ordered for me today, but when I went down there they said its the wrong part and that they dont make the part I need anymore. So does anyone have one? I'm not in the mood to go to a junkyard.Comment
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What valve solenoid? This is a pretty generic term. Are we talking about the thermal blower lockout? That could cause a vacuum leak. Also, they don't make them anymore, afaik.
Really, the only reason your system would intermittently and then continuously go to hot defrost is because of a vacuum leak somewhere.91 Mercury CP, Lopo 302, AOD, 3.08LSD. 3g upgrade, Moog wagon coils up front, cc819s in the back. KYB GR-2 police shocks. Energy suspension control arm bushings. Smog deleted.Originally posted by gadget73
93 F-150 XLT, 302, ZF 5-spd from 1-ton, 4wd.
Daily--07 Civic Coupe. Bone stock with 25k miles
Wife--14 Subaru Outback. 6-speed.
95 Subaru Legacy Wagon--red--STOLEN 1/6/13Comment
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