heater problems

Blend doors working is not an indication that all are good. They must be aligned and move to specific position as designed for system to function correctly. This guide can help us fix it

https://www.2carpros.com/articles/car-heater-not-working

You need to check if any part is out of alignment or dislodged. could be a worn linkage. If the blend motor is working but not getting to correct position, it could be weak or worn and has to be replaced.

My heater blows normal on the driver side and blows cold air on the passenger side also when temp is below minus 20 both sides blow cold air. Do you know if this is a common problem?. I have checked my collant level and it is fine
Theresa

You have a door issue here-could be a vacuum/actuator/HVAC control module-it This guide can help us fix it

https://www.2carpros.com/articles/car-heater-not-working

Please run down this guide and report back.

Just to add my 2 cents on this one. Normally when you have no heat after doing anything to the cooling system it is because you have an air pocket as mentioned prior in the heater core. The best way that I have found to get rid of an air pocket is to use the funnel that you will see attached. This will help eliminate air pockets and I would fill the radiator so that this funnel is a quarter of the way full and then when the thermostat opens, it will pull the coolant in funnel in rather then air. Then you will need to be ready to keep filling it so that it doesn't empty and this will prevent the system from pulling in air. Then you will want to just let the vehicle idle for about 15 minutes with the funnel about a quarter of the way filled and you will see the air pockets working out through the funnel.

Let us know if you still have questions. Thanks

My heater does not blow hot when the fan is turned on. If it is off I can feel the heat from the vent but it will not blow hot. I just had a new Radiator, hoses and a new thermostat put in and it still is not working correctly. Could it be possible that the door that normally opens when I have it set to cold is not shutting? It is very cold and I am at my wits end. Please help

I believe you are referring to the blend air door, and yes that can be what is causing the problem for you. If it doesn't function properly, you won't get heat. Also, make sure that both heater core hoses are getting hot. If they are, then the core is working. If only one is hot, chances are the core is plugged, One last thought. Even though you replaced the thermostat, make sure the engine is warming up to operating temp.

Was driving home from work and notice the heat not working. then as I was going up a hill the car stalled then shut off. Got it back started and was trying to get home and it overheats (starts smoking too) soon as i hit the highway. Tried to start the car and now it’s not turning over. Radiator cap is damaged and I put water in it since I didn’t have coolant with me and when I tried starting the car some came back up.( I do not know if that’s normal)

From the description it sounds like the coolant ran low and you baked the engine. At this point you need to determine a couple things, one is where did the coolant in the system go and second did the overheating cause other failures. If there are no signs of coolant leaking then it could be that you already had a bad head gasket and the coolant was being burned inside the engine. To see what is going on, you can try a couple things. These guides and video can show you the testing required to see where the coolant is going and should give an idea of what the issue is:
https://www.2carpros.com/articles/head-gasket-blown-test
https://www.2carpros.com/articles/radiator-pressure-test

I was driving Friday night and on the way home my car started to steam , so I pulled over and opened the hood and coolant spewed everywhere, I put coolant in and there was a leak somewhere, but I needed to get home, so I put the coolant in, filled the reservoir, and drove home. It seemed to work, the just as I was getting home, the heater started blowing cold air, and the temperature gauge went up again. I drove to advance auto the next day to get a new thermostat and gaskets, and called my friend, who's a mechanic to see she I could get them replaced. The car has been blowing cold since, and the bottom hose remains cold while top gets hot. Is it the thermostat? What else could it be?

Were you able to actually fix the cause of the leak?

There's still a leak. It drips at the bottom. I had the radiator replaced 3 years ago, haven't had a problem since.

You do not have heat because the heater core is empty with coolant. You MUST fix the leak in order to correct your heat issue.

Just above/adjacent to the thermostat housing, you will find a brass plug three prong sensor that is seated in block. This sensor, if bad will shut down the whole cooling system. FYI-Do not replace with generic part-it will not last. Removing the sensor wiring clip is tough. Chances are you will crack the plastic coupling and it goes down hill from there. This is part of the wiring harness and cannot be replaced. The release catch for the coupling is underneath and impossible to get at. First remove the heat cover protecting the wiring, then attempt to release the clip. After that its a piece of cake. Unscrew the sensor, put a new one in. Sensor is not cheap. Get is from Hyundai parts. Good Luck

Replaced thermostat, worked good for one day.

If you have poor heat at an idle and good heat when the engine revs, chances are you are low on coolant. Check that first and let me know what you find.

Joe

I have a 2002 Hyundai Elantra and my heater does not work. The AC works fine. I have none of the main symptoms of a heater core problem. so what could be the problem? thanks KLM.

With the engine at full operating temp, locate the 2 heater hoses where they go into the firewall and feel them to see if they are both too hot to hold. If they are..........

The heat in that vehicle is controlled by a blend door that regulates heated air flow. it is operated by an electric motor/actuator. The problem can be that the actuator is stripped or inoperative or the door itself could be damaged. This is what needs to be determined by examining the actuator and see if it is responding to heat change commands or not.

check the thermostat or change it. and bleed the system

Fan works cold air coming through vents. Air blow to floor and vents correctly by selection.

Hi and thanks for using 2carpros.com

Only a few things can cause no heat, low coolant, a plugged heater core, damaged blend air door actuator, or heater control valve. First, take a look through this link. It describes the most common causes for no heat.

https://www.2carpros.com/articles/car-heater-not-working

Let me know if the link helps or if you have other questions. I attached a picture of the actuator I mentioned. It is responsible for allowing heat or AC into the vehicle. It is located under the dash on the HVAC unit. See pic.

In all honesty, if the coolant is full, and both heater core hoses are hot, this is my first suspect.

Take care.

Joe

I have a 2000 Elantra, I replaced the thermostat and have no heat. Is there a place to bleed the air out of the cooling system.

DRAINING
Remove radiator cap and open heater control valve to maximum heat position. Open drain cocks or remove plugs in bottom of radiator and engine block. In-line engines usually have one plug or drain cock, while "V" type engines have 2, one in each bank of cylinders.

REFILLING

To prevent air from being trapped in engine block, engine should be running when refilling cooling system. After system is full, continue running engine until thermostat is open, then recheck fill level. Do not overfill system.