Car Heaters

Yes, the thermostat is what cycles the water through the coolant system. When u first start your car cold, the thermostat stays closed, this allows the heat from the engine to raise the themperature of the engine to operating temperature. When the system reaches optimum operating temperature, the thermostat opens and allows the hot water from around the engine to move to the radiator and the water that was in the radiator to move to the engine. The water in the radiator is signigicantly cooler because the air from the fan(s) and from the forward motion of the vehicle moves the heat away from the radiator. When the cooler water from the radiator reaches the thermostat it closes to allow the engine to warm up to temperature again. This cycle continues the entire time your vehicle is running. Engines are more efficient when they operate within a certain temperature range. If the engine is too cold, the oil is less viscous and the ionization of the fuel through the fuel injectors is less consistant which in turn provides poor ignition within the cylinder exhausting unburned fuel. If the engine it too hot, the oil breaks down and the fuel prematurly ignites causing knock. Not to mention the fact that your engine will eventually melt.

too much anti freeze has nothing to do with heater. but you should always keep the antifreeze level under the MAX indicator on the reservoir because you need the space for the heated antifreeze to expand and to siphoned back when it's cooled down.

I have the exact same problem with my 86 civic, good luck trying to find an answer from anyone. I changed everything as well, including head gasket. I was told it could be a cracked head so i went to the wreckers replaced the head, TWICE! same problem, think I'm looking at a cracked block...Anyways, make sure you are bleeding the system properly also you might want to get the head pressure tested at a machine shop, not just dye penetrant! Could have a cracked head.... Especially if it has been overheated before

No. Antifreeze is added to the engine cooling system to help the engine run cooler and keep the water from freezing in the winter. A refrigerant (also called freon) is what makes the a/c blow cold air.

The blower may simply have burned out. If the blower is out then the heater probably still works.

I recently installed a new heater core in a 1991 G10 van. I removed the heater fan housing, the heater core hoses, then the compartment came out. After removing the campartment has to be taken apart to replace the core. Alot of work but not all that hard.

First make sure you have the correct temp thermostat for your car. If you went with a cooler one, your heater won't work correctly. If you have the right thermostat, you probably have a bad heater control valve or your adjusting cable isn't connected. Check those things out. Your heater core could also be bad.............if the car is not overheating any more I would check that.

the problem i found was the door on plenum for the air condition was loose and swinging or the step motor link that changes from heat to A/C is loose or off the shaft

look in these areas under dash behind radio and glove box (remove glove box )

Replace the thermostat first. If it is stuck open, engine may not get a chance to warm up.

sounds like the cable from the knob is streached/broken or flap has stuck closed

Low coolant, failed thermostat, missing belt, failed water pump, failed HVAC control, etc

Engine could overheat, can bust your radiator hoses. If ran for long while overheated you could blow the engine.

Hi,U need to find a heater connection that supplys water to heater,it is found on the top of engine,between the heater control unit & engine,its a large tube like a radiator hose,on top of the that is a bleed screw,its actually in the hose,u may have to feel around for it,but thats the bleed point,just unscrew it a bit & water should trickle out,but b careful its very small,so take care,ALB Keithy

SOUNDS LIKE YOU HAVE A CLOGGED RADIATOR WHAT YOU NEED TO DO IS GO DOWN TO AUTOZONE OR YOUR LOCAL AUTOMOTIVE PARTS STORE AND AS FOR A RADIATOR FLUSH KIT AD JUST FLUSH YOU RADIATOR.. you should also check your your head gasket you might be mixing oil with your antifreeze, a simple compression test might answer some question for you If your car is automatic, you may have had the trans cooler tube in bottom radiator tank start leaking trans fluid into the cooling water.

There's a sensor in the duct work behind th glove box under the dash that controls the fan speeds.

It could be that. On my truck I only had the two highest speeds and that's the part I changed.

you may want to have the heating core checked!!it might be clogged up and not letting any hot water passing thru.

Low on coolant.

Bad thermostat.

plugged heater core.

Temp blend door malfunction.

either pull the engine out or if you can jack it up high enough to get the pan off.

first you unhook the two hoses coming out of the passenger side firewall under the hood and connect a hose between them first you unhook the two hoses coming out of the passenger side firewall under the hood and connect a hose between them

It use to be said a high concentrate of gylcol would eat away at gaskets. Not too sure if this is still the case

Normal if your heat is blowing cold air could be several things.However to keep it simple having your cooling system flushed and replace your thermostat and if your radiator hoses are more than 4 years old replace them.If after doing this and the problem persist it could be a blocked up heater core or maybe your waterpump is not circulating the water properly as secondary things to consider.Generally the thermostat is key component that fails and will not alloy the water to circulate thru the engine block and not get hot as it is designed to do.These are the simple things and if your cooling system has not been flushed every 3 years or 30k it is a general recommend.

Depending on your vehicle, the temp blend door actuator could also be faulty.

With the vehicle thoroughly warmed up and running, open the hood and locate both heater hoses (one is a feed and the other is a return). Using your hand, feel each heater hose. If one hose is hot and the other is warm or cold, you have a plugged heater core. If both hoses are only warm or cold, you have a faulty thermostat or your low on coolant. If both hoses are hot, you have a faulty temp blend door actuator.

I am not sure if this is the correct answer or not. But in my 91 Dodge Dakota I thought it was the blower motor so I replaced it and it still did not work. What I had to do was look under the hood for the resistor. On my truck, it was mounted threw the firewall by 2 screws on the passenger side near the top of the firewall and had wires pluged into it. Remove the screws and pull out the resistor and see how it looks. If one of the wires are broken you can simply repair this by bending the broken wire and inserting it into the slot beside where it had prevously been and recrimp the wire inplace. Then put the resistor back into the firewall and you should now have your blower motor working again.

my 2004 Pontiac vibe will not blow heat nor air, worked fine this morning but this evening it quit and won't do anything..

Look to see if you threw a fan belt. Check your thermostat. That is the most likely cause. Then check your water pump.

Yes. The heater core provides the heat which blows out your vents. The heater core has engine coolant flowing through it (it is like a mini radiator) which creates the heat which warms the air that comes out your vents. If you have low coolant, there may be no coolant circulating through heater core, thus causing cold air to blow out vents.