Why does my car AC vent blow hot air when driving even when the AC is off?

Most cars do not have AC vents, only climate control vents.

When it's hot out, air is blown over the AC evaporator before it's sent to the cabin.

If it's cold the air is blown over a small radiator that takes heat from the engine.

The temperature is controlled by the flow over the evaporator or the radiator.

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Why does my b2300 truck blows hot air even when its set to col air?

i would first start by checking the amount of freon the a/c compresser has, it would also be a good idea to flush and refill fill it since you've already gone this far.

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Why is my car AC blowing cold and hot air?

Another cause of AC blows cold then warm An overcharged car AC system can start out pumping cold air.But that cold air turns warm fairly soon after because the high side pressures build to the point that the high pressure switch shuts off the compressor clutch.Evacuate and recharge the car AC sy...

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Why does my AC sometimes blows hot air?

Most likely, if you're having issues with your air conditioner blowing hot or warm air, it's either a problem with the compressor/outside unit or your air conditioner is low on refrigerant.You may also have a return duct that is broken or disconnected and is pulling in unconditioned air from outs...

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Why is my AC blowing hot air after recharge?

It could be an electrical failure in the circuit during charging, overheating vehicle, or maybe the coolant is just low.So, make sure that you check the compressor as it could be the reason why car AC not blowing cold air after recharge.

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Why does your vent blow hot air when it is set on cold?

It depends on what the weather is outside and how developed the air conditioner is. if it's hot out it may take a while to get cool or if it is scorching hot outside it may not get cold at all.

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Why does AC and heater blow air through defrost vents and will not blow air?

depending on what year and make it is, the most likely issue is that you have a valve that moves to divert air to the upper vents, floor vents, and defrost vents and it is either stuck in the defrost position, is broken, or a cable/connector has come loose. The valve is usually in the center of y...

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Always blowing hot air through the vents?

Doors in the kick panels or heater box are not closing to redirect the air.

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Why does hot air come out of my car vents?

Most cars do not have AC vents, only climate control vents.When it's hot out, air is blown over the AC evaporator before it's sent to the cabin.If it's cold the air is blown over a small radiator that takes heat from the engine.The temperature is controlled by the flow over the evaporator or the ...

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AC in my 2002 VW Jetta stopped working. Hot air blows from the vents in interior of car. The AC is fully charged and compressor works please help?

Check your Fan Control Module!!! Check your Fan Control Module!!!

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Why does my truck AC blow cold then hot?

Another cause of AC blows cold then warm An overcharged car AC system can start out pumping cold air.But that cold air turns warm fairly soon after because the high side pressures build to the point that the high pressure switch shuts off the compressor clutch.Evacuate and recharge the car AC sy...

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Why is my air conditioner not blowing air through vents in my car?

Common reasons for this to happen: Blown fuse: Like many electrical units in your car, the ventilation system relies on a fuse for overcurrent protection.If the ventilation system's fuse blows, then the circuit will stop working, and there will be no power for the vents.Bad relay: A bad relay ca...

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Why is my car AC not blowing cold air?

These include: Low Refrigerant: Low refrigerant will prevent your air conditioner from operating (the clutch won't kick in and make the compressor cycle if the amount of pressure in the system is off).This is actually the single most common problem for an AC not to blow cold.The same is true for ...

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Why is my car AC blowing warm air?

Like having a blocked condenser, having broken cooling fans can cause a lack of cooling at your condenser and could cause your car AC blowing hot air.These small leaks can cause your air conditioning system to stop blowing cold air.

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On my 2001 Explorer sport trac the heater or vent only blows hot air now even if the thermostat knob is turned all the way on cold?

It sounds like the control unit is going bad. Replace that whole panel there where the knobs for heat and air are and it should be fixed.

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What does it mean when your car AC blows hot air?

It is used to cool the hot compressed refrigerant back to ambient temperature as it comes from your compressor and uses the air your car is traveling through to do that.Like having a blocked condenser, having broken cooling fans can cause a lack of cooling at your condenser and could cause your c...

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Why does your car blow hot air all the time?

it is drawing the hot air off the engine.

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Why did my car AC stop blowing air?

Turn the car's fan motor on high and press the button to turn on the AC.If it does not turn on, it is an indication that either the switch itself is malfunctioning or the AC circuit is not getting power.Step 2: Verify that air is blowing.Verify if you are able to feel air blowing through the vents.

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Why does your car blow cold air instead of hot air when used?

Could be a stuck open thermostat or low on coolant or the temperature blend door is faulty.

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Why does your aircondition blows hot air?

Two basic reasons:

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Why does my car blow out cold air when idling?

Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.

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My car is blowing out cold air not hot when the heater is on.?

You need to change your thermostat in the car.

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Why is your car air conditioning blow hot air?

because you need to keep warm when it is winter and other times when it it cold

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Why is your ac blowing out of dash vents?

Your AC might be blowing out of dash vents on the windscreen as you might have turned the knob to that particular mode. It is also possible that the vent mechanism might be out of order or broken.

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What does it mean if your car AC is blowing hot air?

Like having a blocked condenser, having broken cooling fans can cause a lack of cooling at your condenser and could cause your car AC blowing hot air.These small leaks can cause your air conditioning system to stop blowing cold air.

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Why does your truck blow heat even in ac mode?

The heater control valve is stuck open.

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Why does my car shut off when it gets hot?

Well, there is an ignition problem that can cause this when the engine gets hot and it stalls.It's caused by a lack of spark which can be either the ECU's fault (on EFI cars), or the coil on pretty much any car.Heat causes expansion.An engine needs more fuel when it's cold than it does when it's ...

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Why does my air vent smell in my car?

Mold and Bacteria Probably one of the reasons why there is a distinct smell in your air conditioner when you turn it on is the growth of mold in your air vents.Smells of mildew in your car may be caused by the growth of bacteria.The growth of these bacteria is often behind the dash panel on the ...

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Why does my AC stop working when it's hot outside?

So now the refrigerant can't absorb more heat from your air, causing your air conditioner to blow out lukewarm air.Or worse.Your air conditioner will keep running until it overheats because it can't reach your thermostat temperature setting.Solution: Clean your outside unit using a special coil c...

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Why did my AC stop blowing cold air?

The most common cause of window air conditioners not blowing cold air is a lack of adequate air flow.If the air filter is dirty or clogged, there may be little or no air flow over the evaporator coils, which may cause them to become too cold and frost or ice can form on them, restricting the air ...

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Where can you find a hot wire that is hot even when the car is off?

Look on the main fuse panel, you should find a place there.You can also probe the fuse box with a test light.The wire that goes from Battery pos. to ignition switch

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Why does my heater in my car blow cold air?

Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.

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Why is my AC in my car not blowing?

The lack of precious cold air could be caused by: A Freon leak caused by a failed o-ring, seal, hose or component.A clogged expansion tube or refrigerant charging hose.Failed compressor or compressor clutch.

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Why is your air in your truck not blowing air through the front vents?

Many vehicles use engine vacuum to operate the HVAC functions. If the vacuum supply is cut off for whatever reason the HVAC system defaults to the defrost mode only. Look for a disconnected, cracked or pinched HVAC vacuum supply line under the hood.Also, if the vehicle has a cabin filter that is ...

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What causes the front air conditioner on 1999 Lincoln navigator to stop blowing through the ac vents and start blowing through the defrost vents?

When there is a problem in the vent system it defaults to defrost setting. Check the doors & vac supply

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Why does my 97 Ford Fiesta heater only blows hot air?

Usually its the heater control valve (£30-£40 New). Its just behond the bulkhead at the centre of the engine bay.However you should put a multi metre accross the control plug first. Make sure it gets a 12v pulsing signal when the heater is set on hot. If not then it's a problem elsewhere. (Possib...

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Why does the ac work when parked but when you drive your car it blows hot then cold and idle goes up and down?

Many ac systems use engine vacuum to operate the ac controls. You may have a cracked or disconnected vacuum line that feeds the HVAC system. Check the vacuum lines under the hood, that is where they would most likely be damaged. A vacuum leak would also be the cause of the erratic idle.

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Why is the air conditioner in a car blowing out hot air?

it simply means you have to add freon to ur air conditioner....you can buy freon at any auto parts store.

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What causes the air conditioner on a 2003 Chevy trailblazer to stop blowing through the ac vents and start blowing through floor and defrost vents?

Check for a vacuum leak -sounds like it is starving for vacuum and reverts to the default position

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Why would the air conditioning only blow air from the defrost and floor vents and not the dash vents?

I would think that is a vacuum or a linkage problem with the heater control assembly (where all the buttons/slides are for changing between floor/defrost/vent) Had a diaphragm go bad on one once, and in a jeep cherokee, a slight collision with a guard rail knocked a vac line off for the vent cont...

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Why does my car keep driving even when I put my foot flat on the brake?

the brakes on your car are broken, any fool with at least an ounce of common sense would have realised this, get them fixed before you kill your self or any innocent bystanders!

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Why does the drivers side blow air cond and the pass side blow hot air on a 2005 escalade?

One side has a faulty temp blend door actuator.

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Why is my AC blowing fog?

Sometimes, when the conditions are just right, the air coming from your A/C unit is drier than the warm, moist air near the vent opening.When the cold dry air comes in contact with the warmer, more humid air, causing water vapor to form and condense into visible droplets, or what we know as “fog.”

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Why does my car turn off when the AC is on?

It may be from low power to the computer, a faulty fuel pump due to bad connection, or a low battery.The blower fan draws a lot of current, perhaps that is dropping the voltage suddenly and causing some electrical component in the ignition system or the anti theft system to shut down the car.The ...

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Why does a 1997 Lincoln town car air conditioner cool blow hot air?

Your air conditioner might need to be recharged. First try putting in a new fuse for you air conditioner in the fuse panel. Alot of people don't know but before turning off a car or starting one they tend to leave their air conditioner on which burns them out over time. Also whats a good idea, ev...

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Why would the ac and heater blow air through the defroster or the dashboard vents but not through the floor vents.?

It should blow through the floor vents. Modern vehicles generally use movable baffles in there HVAC systems, to direct air flow where the controls indicate. If the controls allow airflow to the floor, but nothing flows out, there is a malfunction between the control switch and the actuator that d...

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Why does ac change to defroster vents when it accelerates?

You have a vacuum leak in the HVAC (Heating, Ventilation, Air Conditioning) system. Inspect the vacuum hoses that operate the HVAC system looking for cracked, pinched or damaged hoses. Also inspect the vacuum reservoir for leaks or damage.

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Why does my 2005 Ford focus blow cold air in idle and very little warm air when driving?

Could be,low on coolant,stuck open thermostat,plugged up heater core,temp blend door malfunction,

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In my 2002 the light for your ac on the dash flashes and the ac blows hot air What is your problem?

you need to recharge the ac system. It may have a leak somewhere. take it to a shop that does ac work

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Why does my 2004 F250SD 6.0 Liter AC blow hot with the low side pressure at 110?

the low side pressure should be no higher than 42 psi with the compressor running. if the a/c clutch is engaged, the orfice tube is bad or the compressor is bad

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Why is my AC blowing colder?

A small refrigerant leak is the most common reason a car's A/C gradually loses its cool.A leak in your A/C system could be causing the unit to blow warm air, since there isn't enough refrigerant in the system to cool things down.

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What is wrong when no cool air is blowing out of vents when the ac is on in a 2000 Sable XL?

You may need to have your AC charged

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Why is my car blowing out cold air when the heat is on?

Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.

Read more

Why does my car heater blow cold air?

Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.

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Why is a 1999 Ford Explorer not blowing hot air?

possibilities include thermostat stuck open (temp gauge would be reading cold), low coolant level, blockage in heater core, or temp door in dash broken(very likely on this vehicle)

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Why is my car blowing oil out the air filter?

Could be,Excessive blow-by from worn piston rings and valve guides.PCV system restricted or inoperable.

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Why is my AC blowing out smoke?

When the cold air hits the warm air, white smoke or fog can develop.Then, they condense in the air as water droplets producing the smoke or fog.If your indoor humidity is higher than normal, this can make the smoke even worse.Low fan speed and clogged air filters due to dirt buildup can also aggr...

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Why is the heater in my car blowing cold air?

Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.

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What is wrong if your AC suddenly will only blow air from the heater vent below the dash?

You knocked th avacuum line from the intake to the resirvoir to the inside of the car of. Find it and reinstall it.

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Why does your car a c blow hot since you installed a new alternator?

You may have accidentally unplugged your A.C. compressor or routed the serpentine belt improperly.

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Ac working fine but air barely blowing out of vents ram 2500 diesel 2006?

sounds like the blend doors arent working in the heat/ac plenum. take a look at all your door motors and see if they are connected and working properly

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Why is my car blowing cold air when the heater is on?

The air is then heated by the coolant and then, in turn, warms up the interior of the vehicle.This is the reason that it takes a while for heaters to start blowing warm air.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater...

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Why is your 1995 Pontiac Bonneville blowing hot air with AC on and ext temp is blinking?

low refrigerant charge?

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Why does the car heater blow air through the vents and defrosters but not on the floor?

Check for a vacuum leak either under the hood or under the dash areaCheck the operation of the vacuum actuated motors under the dash areaCheck the operation of the selector switch

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Why is the air conditioning blowing only through the windshield vent 2000 mercury sable?

Many of these systems rely on a vacuum supply from the engine to operate the doors that change the direction of air. When the vacuum supply is cut off the system defaults to defrost mode. I would suspect you have a disconnected, pinched, cracked or broken vacuum line under the hood from the engin...

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Why the a c blown hot air lincoln2003?

it usually means your ac system needs to be serviced. any easy procedure where someone refills the refrigerant in your system.

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Why does air condition in 2000 Hyundai elantra blow hot air?

Either the compressor pump is not working or, more likely, the coolant has discharged to atmosphere. It doesn't have to go to a dealership, most local garages will check and recharge the system and there are some mobile specialists around too. Check your local Yellow Pages.

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Why does 2000 Buick Lesabre Custom Air Conditioner blow only through defrost vents?

The vacuum supply line from the engine is disconnected or broken. When the vacuum supply is cut off the system defaults to the defrost mode.

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Why does my AC only blow on high?

Remember though that bad resistors can be caused by blower motors with a lot of mileage on them.They build up higher resistance and that extra draw can destroy resistor.If that should happen, you may need a new blower motor.To get to the resistor, open your glove box, squeeze in both sides and le...

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How do you get my heater to blow hot air?

Most like a duct problem. Check cables behind control to ensure smooth operation of all doors. The heater core is hot so something is blocking the air or it is being channeled improperly.

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Why does your 1995 Cadillac eldorado blow hot air only out of the defrost vents no mater at what temp i set it to?

likely thermostat is stuck.The temp blend door actuator has failed.

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What does it mean when a car gets hot but blows cold air?

The Air Conditioner is on

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What is wrong when not much air is coming out of your vents in your car hot or cold air?

your blower motor is stuck on low

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Why is my heat blowing cold air?

Your furnace may be blowing cold air because the filter is too dirty.A dirty air filter blocks airflow over the furnace's heat exchanger, causing it to overheat.If the pilot light isn't lit, then the furnace's burners won't light, meaning no heat.

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What is is the heater blowing cold air when its set to the hot position?

Either the temperature blend door is not working, the thermostat is stuck open or you are low on engine coolant.

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What does it mean when your AC is not blowing cold air?

1.Wrong Thermostat Settings.If your air conditioner isn't blowing cold air, the answer could be as simple as your thermostat being on the wrong setting.Setting your fan to “AUTO” will not only save you money, but it will also ensure that your fan is only running when your air conditioner is cooli...

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1993 Toyota Corolla is blowing hot air?

If your 1993 Toyota Corolla is blowing hot air, it might have a refrigerant leak in the cooling system. You can try replacing the refrigerant with a kit found at most auto parts stores, but if the leak is large, this fix will not last long. You might also have a compressor failure.

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Why is my car heater not blowing any air?

Basically it's a small radiator that hot coolant flows through.The fan inside your car then blows heat off of it to give the cabin heat.If your car is running low on coolant, if there's air in the system or if the core itself isn't working properly, then this could be the cause of your car heater...

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Why does Car runs hot when air conditioner on?

The ac unit is a tax on the engine to run. This is true with all vehicles. Having the ac on will make the engine work harder to run the ac compressor. This makes the engine run hotter.

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Why is my car blowing out cold air?

Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it.It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.

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Why is there no air blowing in my car?

The other main way that car heaters malfunction, other than blowing cold air, is to not blow at all.This is typically due to a bad blower motor, but it can also be caused by a handful of other related components.If you are able to determine that your blower motor is receiving power, then it is pr...

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Why doesn'tMy blazer blows air it just doesn't get hot?

Low on coolant or bad thermostat or plugged heater core or bad temp blender. Check in that order.

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Why does my car vibrate when AC is on?

Typically when the AC compressor is cycling, it will draw more power from the engine, which might make an existing rough idling engine "feel" worse.This could be caused by fuel system components like mass air flow sensor, fuel injectors or even the EGR valve being clogged with excessive debris.

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Why does my car hesitate when AC is on?

Bad Belt: One often overlooked cause of a car surging with the AC on is actually a worn compressor belt.If the belt is stretched or worn smooth, it can slip during operation.Overfilled AC System: While low refrigerant can cause problems with your AC and engine surging, an overfilled system can ca...

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Why won't my AIR conditioner blow COLD air when pressing on the gas?

You may need to get your freon recharged or your A/C compressor might be bad.

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Why is air not coming out of my vents?

Low Air Flow Through Vents In House And Other AC Problems.The most common cause of low air flow through the vents in your home is blocked or dirty AC filters.If your AC is running but is not cooling the house properly, you could be the victim of a variety of issues.

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What causes the air conditioner to blow hot air then cold the car is also running hot since this happened?

Cars now have 2 cooling fans 1 for the engine and the second comes on when you run the a/c.You need to check if both fans are running when the engine is started and a/c on. If 1 is not check all the fuses.99% of the time the fuse blows.The fuse will be a larger amp and probably under the hood. Ho...

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Why does my car run slow when AC is on?

Cars RPM drops when the AC is turned on because the AC compressor has kicked in.Energy diverted from the engine to power the air conditioner refrigerant compressor., assuming the car doesn't compensate for the additional load by slightly increasing the throttle to match.

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1994 mazada protege ac compressor comes on but still only blows hot air?

If the compressor ls operating then either the heat control is stuck on heat, or the diverter door is not opening. Turn on the heat an see if the heat temp will go up and down, If its ok then a door is probably stuck in heat mode. Check for vacuum leaks, as the door operates on a vacuum.

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Why after replacing my battery does it shut off when i turn the ac on?

t is probable that your wires are not properly grounded. Check the wiring and ensure that they are properly grounded. Antolin Andrew Marks.

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Your 95 lesabre starts off blowing out cold air then it turns to hot why is that?

try adding ( 1 ) can of 134A freon sounds like the system is low.

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Why is cold air blowing when the heat is on?

Repeated overheating will hurt the furnace's heat exchanger, which is expensive to fix.3) Pilot light is out If your gas furnace is only blowing cold air, then the pilot light may be out.if the switch is on, then check to see if the pilot light is dirty.if it is, clean it to allow gas to come thr...

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Why does car turn off when I turn on AC?

It may be from low power to the computer, a faulty fuel pump due to bad connection, or a low battery.The blower fan draws a lot of current, perhaps that is dropping the voltage suddenly and causing some electrical component in the ignition system or the anti theft system to shut down the car.The ...

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Why is my central AC not blowing hard?

Dirty evaporator coil Your evaporator coil needs air to blow over it to complete your AC's cooling process.If it's clogged in dirt, airflow is blocked, weakening the air you feel coming from your vents.This is often caused by running your system with a dirty air filter (or no air filter) for a l...

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Why is smoke coming out of my air vents in my car?

Fog or smoke coming out the air vents is caused by cold dry air coming in contact with warmer, more moist air near the air conditioner.If the air temperature near the unit is below the dew point, this causes water vapor to form in the air and condense into water droplets, thus causing the fog or ...

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Why does your radio not turn off even when the car is off and the door has opened?

because you have the radio wired to a constant hot wire .

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Why is your car blowing steam out of your vents?

The heater core is leaking coolant.

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Why does the heater not blow air?

The heater does not blow air because it emits infrared rays that have heat molecules within them, thus releasing heat, not blowing it. A heater does not blow air becasue there is no moving air source within the heater. The heater emits infrered rays that cause heat to slowly flow out of the heater.

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Why does my clutch judder when hot?

Re: Clutch judder when warm/hot, what needs replacing?? Most likely the clutch cable conduit.When the engine rocks with pulling away from standstill the bend in the clutch conduit allows for a bit of give on the cable without causing the pressure plate to get depressed slightly on and off hence ...

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Why does my car blow smoke when I accelerate?

However, thicker smoke is a big problem, and can be caused the engine burning coolant.This can be the result of a serious issue like a blown head gasket, a damaged cylinder head, or a cracked engine block – all of which are costly repairs.

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What causes your front ac vents not to blow a lot of air on a 1995 ford E 150 van?

Faulty blend door control, clogged cab filter, weak HVAC blower, obstruction in the HVAC ducts.

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