Question about 1991 Cadillac DeVille

3 Answers

Heater don't heat

Replaced heater core checked the box under the glove box it moves car shifts from defrost and heat in the vents and on the floor fine just not hot at all in fact the air conditioning works well in all these positions where do i look for another place to get the hot air into the system? Is there a place I can go to and get a look of the system and show all the workings I could probably solve this. help!!!!! please.

Posted by on

  • ginirb Nov 18, 2008

    My Caddy Deville (1991) heater blows, but it is cold. The air seems to vent through the floor vents some and the defrost, not any through the middle vents in the dashboard. And, the air is cold. My air-conditioner works well. Just no heat. It just stopped working one day. I'm cold!

  • jwblackst Dec 13, 2008

    my 1993 caddy blend door was fixed quickly at the dealers shop 2 years ago, but now it's doing the same thing, blowing cold air!!! any help will be appreciated.. thanks john

×

3 Answers

  • Level 1:

    An expert who has achieved level 1.

    Corporal:

    An expert that hasĀ over 10 points.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 18 Answers

Check t stat by boiling it in water if it doesnt open theres your prob

Posted on Nov 13, 2011

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Did this solve the problem, the blend door. I have a 1993 Cad DeVille with the same problem. The Core has been change 2 x by other owner and it has only 94,000 miles on it.

Posted on Nov 07, 2008

  • Level 1:

    An expert who has achieved level 1.

    Corporal:

    An expert that hasĀ over 10 points.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 7 Answers

Check to see if water is circulateing threw heator core while car is running with heat on feel the heator hoses were they go threw fire walland make sure they feel hot andbe careful you dont burn your self if they are cold replace heator control valve if hoses are hot then you have a blend door prollbem

Posted on Oct 07, 2008

1 Suggested Answer

  • 162 Answers

SOURCE: blowes air throught defrost vents only

its a problem with the switching mechanism. you have to look up under the dash to see if you can see where the switching mechanism is. if you can not see it from there youll have to remove complete center dash

Posted on Apr 04, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Where is the heater control valve located?


If you are trying to locate some kind of water valve that routes the hot water to or away from the heater core, no such animal exists anymore. Hot water is always routed thru the heater core whether or not you are using the heater. The blend box under the dashboard has flappers that move to route air either thru the heater core, the A/C evaporator, or thru a bypass that routes around both. The blend box allows you to set temperature by adjusting the flappers. It also controls where the air goes; defroster vents, floor vents, or dash vents. If you are not getting heat, the problem is most likely that the blend box flapper is not operating correctly. This could be due to a sticky linkage, a bad vacuum motor, or a faulty control head. You could also have a clogged heater core, or a thermostat that is stuck open all the time. If you are getting heat and don't want it, the blend box flapper is also the most likely cause.

Oct 18, 2015 | 2003 Chevrolet Malibu

1 Answer

Heat wount come out of floor ventjust defrost vent


First thing I'd do is check the vacuum lines on the vacuum reservoir under the hood, then the heater box vacuum lines. Replace any bad ones you find. Run the engine and see if there is a good vacuum coming to the heater control. The doors that move the heat up and down to the vents, defrost, floor etc are run by vacuum. If you don't have vacuum there, check the vacuum lines under the hood and repair as necessary. Good luck.

Oct 23, 2014 | Cars & Trucks

1 Answer

2002 Lincoln Town Car I have hot air blowing from the vents.


Check you blend door under the glove box see if its opening and closing

Apr 03, 2014 | 2002 Lincoln Town Car

1 Answer

1999 escort heat shift from floor to defrost


you have a vacum leak check under the hood usally they make a whistling noise. Im sure one is off or broke. if this was helpfull please leave me good feedback ps the broken line could be under the dash usually on passenger side going to heater box. but the problem is usally under the hood. check hose on pcv valve

Feb 20, 2013 | 1999 Ford Escort

1 Answer

Heat stopped working in 2000 pontiac sunfire


With blower on high and tempature to max heat check to see if you have good air flow in all mode selections (defrost, vent, floor etc.). If so and you still have no heat then check heater core hose going from engine to inside car to heater core with vehicle running and coolant tempature about half on guage. If both hoses are hot and coolant in radiator/overflow bottle is full then hot cold blend door is stuck in cold position. If coolant level is low you will get no heat, check coolant level first.

Dec 18, 2011 | 2000 Pontiac Sunfire

1 Answer

Climate control system blows only through the defroster vents and not through the passenger compartment vents; the windshield fogs in high humidity and windshield wipers are necessary to clear the fog. ...


If the fogging is plain moisture and not coolant (it would take on a green hue and you would smell coolant if this is the case) than the issue is with the blend door actuator. This component diverts air from the window, to the vents and floor. You may have a "stuck" door or a defective blend door. If it is coolant you are seeing (smelling), you may have a bad heater core. When bad, a heater core will dispel green vapor through the defroster vent.

Assuming the problem is merely the blend door, you may be able to free the part (if it's stuck) by locating it (usually under the glove box or between the glove box and middle console.

Jul 31, 2011 | 2006 Mercury Grand Marquis

1 Answer

Passenger side heat doesn't work in my 2007 Dodge Grand Caravan. There is no heat, only cold air, coming from the dash, floor, & defrost vents. There are dual temp controls for the driver &...


I really can't be sure off hand, but what you wrote looks like the control valves are sticking(these flaps allow air to go different directions at the vents). its located at the heater core(towards the left side of the heater core) under the plastic just under the dash. you can manually move them, encase they are stuck, they do stick sometimes. while checking the vent doors, make sure your vacuum lines are connected. also check to make sure your vent hoses are tight. I hope this helps

Jan 11, 2011 | 2007 Dodge Grand Caravan SXT Minivan

1 Answer

2002 Mitsubishi Lancer leaking water under glove box and a noise in that same area becoming more noticeable. Air conditioning unit?


Typically, when you have water leaking from underneath your glove box, that means that your heater core is leaking. Your heater core is basically a small radiator located inside your car, just behind your glove box, thjat a fan blows through for the purpose of warming the interior of your car and defrosting the inside of your windshield. This core is fed water via your engines water pump, from your engine where the water is heated, through the heater core and back through the radiator located under the hood of your car and through the engine once again, in a continual cycle. What happens after time, the heater core is of a much thinner construction than your radiator and will corrode through in a much lesser time. The other things which commonly occurs in the heater cores today, is that when your car overheats or blows a head gasket, it will allow the exhaust gas from your engine into your water system and create a tremendous amount of pressure. The heater core is not designed to deal with this extra pressure and typical blows out and leaks water onto the floor board of the passenger side of the vehicle. Heater cores are not all that expensive a part, but to replace it, can be quite difficult on some make and model cars. This information applies to most all make and model cars both previously and currently produced.

Jul 17, 2010 | 2002 Mitsubishi Lancer

1 Answer

98 chevy tahoe 4x4 defrost quit working. I get heat for the floor and from vents , but not the windsheild defrost . Please help ronandtheresa@gmail.com


Check blend door motors under dash on heater box. Move heater control and see which one is not moving. That's the one thats broken or sticking!

Mar 02, 2009 | 1998 Chevrolet Tahoe

2 Answers

Heater control 98 chevy s10 blazer


These trucks have a problem where moisture builds up in the heater box then freezes. When this freezes and you change your heater settings it breaks the shaft for the blend door. If this is what happened you should be able to look under the dash above and to the right of the gas pedal and you will see two vaccuum accuators one of them you should be able to wiggle around the linkage if it is broke. To fix this you need to remove the entire dash to get the heater box out which involves discharging the AC and draining the coolant because the heater core and evaporator come out. Please rate.

Dec 13, 2008 | 1996 Chevrolet Blazer

Not finding what you are looking for?
1991 Cadillac DeVille Logo

233 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cadillac Experts

yadayada
yadayada

Level 3 Expert

60667 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21936 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6811 Answers

Are you a Cadillac Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...