Broken heater

When running my heat it comes out cool/Luke warm. My coolant levels are where they should be and I've even tried to release air pockets within the system nothing is working. My car gets to operating temperature just fine and both the in and out hose on the heater core get hot. I've considered a flush but since both hoses are warm I assumed there wasn't any blockage. Any advice? SOS it's getting cold outside

My car has 140000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
If everything in the cooling system has been eliminated as a cause – coolant level, flow, thermostat operating properly, etc., the issue may lie with the heater controls inside the vehicle. Within the "heater box" under the dash is located the heater core and air conditioning evaporator. The blend door is responsible for diverting the air flow between the evaporator for cold air and the heater core for hot air. If the blend door is not moving properly to divert air through the heater core to get hot, then you can still be getting a mix of cool air albeit cooled air if the A/C is on, or simply outside air. Possible causes for the blend door not moving properly can range from the hinge mechanism itself binding or broken, or the cable and/or electrical signal to actuate the door being at fault. Have a certified technician inspect the heating system to locate the cause.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

The most common reasons a Dodge Nitro heater isn`t working are a broken heater blower motor, a problem with the thermostat, or a failed heater blower motor resistor.
If your coolant level is a-okay, but your car heater is blowing cold air and your engine is overheating, then you have a clog in your cooling system. Conversely, if your engine temperatures are unrealistically low after a drive, your thermostat is likely the culprit.
Low Coolant Level

If there isn`t enough coolant in your system, the heater core will blow cold air into your car. Solution: If you confirm that a low coolant level is the source of your problem, you simply need to top off your coolant. You may want to check for leaks as well if you just recently refilled your coolant.

Contaminated Coolant

Over time, contamination in your cooling system can make your coolant more susceptible to freezing, which may result in your engine overheating and your heater not working!

Changing the blower fuse

If you think the cause for your car heating not working is related to the blower fuse, be sure to replace it with one of the same amperage. The fuse may have blown due to age, or it may suggest an underlying problem.

A faulty or broken thermostat is the most common cause of your car`s failing heat. Stuck open or stuck closed, the part can not only cause issues with your heat but also with your engine`s cooling system.
Troubleshooting Tips For Furnaces Not Blowing Hot Air

Make sure your thermostat has not been set to a lower setting by someone else. Check your thermostat`s batteries and replace any that are exhausted or defective. Clean all of the parts of your furnace, especially the ones that are susceptible to dust and dirt.

If you find your furnace blowing cold air, you may have a dirty or clogged air filter. To make sure, remove the air filter and inspect it. If it`s clogged with dust, clean it with compressed air or wash it in warm water with mild soap or just buy a new one.
The most common reasons a Dodge Ram 1500 heater isn`t working are a broken heater blower motor, a problem with the thermostat, or a failed heater blower motor resistor.
Common Car Heater Problems

The heater switching system might be faulty. The cabin air filter might be choked, restricting the airflow through the heater core. The thermostat valve might not be working right. The heater core might be clogged.

Your car is overheating.

Lastly, a sure sign of a bad heater core is when your vehicle overheats. This could be due to a blown head gasket or a plugged heater core issue. Do not drive your vehicle if it continues to overheat, and make sure to bring it in to your local automotive repair shop as soon as possible!

A car A/C blowing hot air is often the result of a refrigerant leak. Refrigerant is a liquid that circulates through your car`s A/C system, expanding and contracting as it removes heat and humidity from the cabin. None of the other A/C components will function correctly without proper refrigerant levels.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Overheating issue, when heater is on its normal temp. but if heater is off it begins to overheats, until heater is turn on again.
ANSWER : It sounds like your engine might have a restriction in the cooling system. If the cooling system has a restriction that prevents its flow, this will cause the engine to get hot. The heat is dissipated from the cooling system by means of the radiator.

When a restriction exists sometimes the radiator alone is not enough. The heater core is like a small radiator inside the dash and is also another means of dissipating the heat from the cooling system. So essentially when the heat is on you are introducing a second radiator into the system which will help to cool the engine down.

In order to get this fixed, consider YourMechanic, as one of our mobile technicians can come to your home or office to diagnose the overheating issue firsthand and help you make the necessary repairs.

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Overheats when heater is on, heater blows cold air.
ANSWER : Since you had cooling system work done recently, one possibility is the cooling system is air bound. If air is trapped within the cooling system and not properly bled from the system after a repair, the air can cause the coolant to not circulate properly. This can lead to overheating and no hot air from the heater. Another cause that can simply be coincidence is a stuck thermostat. The function of the thermostat is to allow the engine to reach a certain temperature before opening and allowing coolant to flow throughout the cooling system. If the thermostat is stuck closed and fails to open, the coolant will not flow properly and cause the engine to overheat. The heater will blow cold air because hot coolant is not flowing to the heater core behind the dashboard to provide heat for the interior. Have a certified technician diagnose the engine overheating as soon as possible. Continued driving while overheating can damage the engine.

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Why is my car heater blowing cold air? I start my car, give it a few minutes and the heater never heats up.
ANSWER : The lack of heat being generated by your system may indicate a clogged heater core. The [heater core]((https://www.yourmechanic.com/services/heater-is-not-working-inspection) is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower motor that blows the warm air through the vents inside the car. The other possibility is that the thermostat may not be allowing the engine to reach a normal operating temperature and since the engine’s warm coolant is the essential source of the heater core supplying heat to the inside of the vehicle, this can impact the warmth of the heat inside the vehicle. I would suggest having an expert from YourMechanic come to your location to diagnose your heating system.

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Heater blows cold when temp gauge is halfway. both heater core hoses are hot.
ANSWER : If both heater hoses are hot then the core is getting hot coolant flowing through it. You should check the temperature blend door actuator behind the glove box on heater case to see if it is operating the temperature blend door or not. If the actuator is not moving then replace actuator and retest the heater output.

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Nissan altima 2013 rear seat latch is broken and I cannot fold down the seat. How do I repair the broken seat latch? What should I
ANSWER : Hello, thank you for writing in. Correcting the issue will involve finding out what the exact issue is first. The latch has a handle that is pulled to release it. If the handle is broken, and you cannot release the latch, you will need to replace the handle. They typically screw or bolt on with ease. If the latch itself is broken, then you will have to manually release the latch with a screw driver or other means first before replacing the entire latch unit. For more help with the repair, contact our service department to schedule an appointment.

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turned heater on small amount of smoke came through vents checked radiator levels were fine
ANSWER : Hello, thank you for writing in. The vents can pick up all sorts of fumes, smoke, and smells from the engine bay and blow them into the cab. If the smoke you saw was related to the cooling system, its likely the coolant level would be lowering. The smoke you are seeing has to come from something burning. Keep an eye on the coolant levels, but check ALL fluid levels as well. It may be something else that is burning. Does it have any smell characteristics that may be used to identify what is burning? You may need to run the car in order to diagnose the issue. The heater core is one of the last components before the air is blown into the cabin. These units are notorious for failing and leaking. Again, if this were the case, you would see a drop in coolant eventually. Its likely if the heater core is to blame, that you will not see the level drop if you are not running the heater. You will likely have to turn the system on low and see if you can identify the issue.

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Weak heater, is this a defect?
ANSWER : Having a poorly performing climate control system can be difficult. From what I’ve found, Nissans generally don’t have the best performing climate control when it comes to the heater. You’v stated that it can blow cold on one side and warm on the other. If you have dual zone climate controls, make sure they are set to the same temperature. If the climate zones are set the same, or you have a single zone climate control system, a trip to the dealer might be necessary to check the operation of the climate control and see if Technical Service Bulletin (TSB) NTB14-113 applies to your vehicle.

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Black soot and bad smell coming from the heater vents.
ANSWER : Hi there. Sounds like the cabin air filter to the heating and a/c system is degrading and peeling apart. The stuff that is coming out into the cabin area is a filter full of dirt and debris. I recommend replacing the cabin air filter and the black sooty stuff will stop coming out. Old filters will make a bad odor in the cabin area, especially when the filter gets heated up.

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