While driving defroster set to hot blows hot air as it should, while idling it is blowing cold air.
While driving defroster set to hot blows hot air as it should, while idling it is blowing cold air. When I stop at a light the air almost immediately becomes colder, as I accelerate the air begins to get warmer, seems to take longer to switch from cold to hot than it does to switch from hot to cold. There is no change in fan speed. The car never did this before.
My car has 108000 miles.
My car has a manual transmission.
Experienced mechanics share their insights in answering this question :
First, the coolant level should be checked to make sure the radiator is full. While the overflow tank may be full, the radiator cap must be taken off to check the level inside the radiator. If you find the level is very low, you have a coolant leak that must be fixed. If coolant levels are normal, an engine thermostat or heater control problem may be what you’re experiencing. Consider hiring an experienced technician like one from YourMechanic who can come out and take a closer look at your lack of heat concern to offer a more personal diagnosis.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
That means that the ignition system is working, so you most likely have a fuel system problem. What you want to do is pressure test your fuel pump.
Faulty heater cores and low or contaminated coolant levels often come hand in hand, and both issues may lead to your engine overheating and your heater not blowing hot air.
The most common reasons a Jeep Liberty heater isn`t working are a broken heater blower motor, a problem with the thermostat, or a failed heater blower motor resistor. Search our network of RepairPal Certified shops near you to speak with a technician about your issue. Oops!
You Have Cold Air Blowing Out The Vents When The Heat Is On Because of a Dirty Air Filter. Hiding in the filter of your heating system is dirt and debris. If you aren`t cleaning it regularly, this will accumulate over time, leading to problems with your heating system`s efficiency.
Across almost all models of cars and trucks, the number one cause for a vehicle`s heater to stop working is a faulty or broken thermostat.
If you turn on the system and don`t feel any warmth, it`s possible that the heater core is not functioning properly. Other signs of a failing system include a coolant leak, a sweet, syrupy smell inside the cabin, foggy windows, and an overheating engine.
It`s most likely an incorrect thermostat setting if you find your furnace blowing warm air, not hot. The fan is set to “on” instead of “auto.” Furnaces only pump hot air until the thermostat setting is reached, so if your fan is always on, it will blow both hot air when the furnace is heating and cold when it`s not.
If your heat pump is not blowing warm air, the refrigerant may be the problem. The unit could be running low and need additional refrigerant added. Needless to say, this isn`t something you can do on your own. A refrigerant leak can cause this problem.
Begin by turning the power off to the heat pump. You will need to reset both units by pressing the buttons or flipping the switches. If your heat pump does not have a reset button, it will have a power switch. Turn the switch off, wait for two to three minutes, then turn the switch on again.
Run the Fan
One thing you could try to do to unfreeze your heat pump (if your system is equipped with it), is simply turning on the fan. Blowing air will usually thaw the equipment within 60 minutes.
Start your car`s engine and allow it to idle. Look through the radiator filler neck to see if the coolant flows. At this time, it should not be flowing as your car has not reached the operating temperature to cause the thermostat to open. If you find the coolant is flowing, it means the thermostat valve is open.
Water by itself can`t do the job of antifreeze due to its lack of boiling and freezing point range and its inability to protect your vehicle`s engine. Plus, it doesn`t absorb heat as effectively. In the case of an absolute emergency, you can use water in your coolant rank.
It sounds counterintuitive, but Reina recommends turning on the heater. It draws warmth away from the engine and into the passenger compartment, lessening the burden on the engine`s cooling system. In certain circumstances, that may be enough to reverse the overheating, he says.
Nationally, you can expect to pay about $550 on average for a blower motor replacement, including labor. However, if your unit is under warranty, you might get away with a labor-only charge of as little as $130. More complicated units, or units that are difficult to access, can cost as much as $2,000+ to replace.
The average cost for a Blower Motor Replacement is between $329 and $348. Labor costs are estimated between $68 and $86 while parts are priced between $260 and $262.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
While driving defroster set to hot blows hot air as it should, while idling it is blowing cold air.
ANSWER : First, the coolant level should be checked to make sure the radiator is full. While the overflow tank may be full, the radiator cap must be taken off to check the level inside the radiator. If you find the level is very low, you have a coolant leak that must be fixed. If coolant levels are normal, an engine thermostat or heater control problem may be what you’re experiencing. Consider hiring an experienced technician like one from YourMechanic who can come out and take a closer look at your lack of heat concern to offer a more personal diagnosis.
Air conditioning blowing mildly cold air on the coldest setting, turned off/on again, now blowing cold air, should it be checked?
ANSWER : If you are getting ready for a long trip and suspect the cooling fan may be not coming on for the radiator and a/c then you should have the a/c and cooling system performanced checked before trip. Nothing worse than breaking down when out of town in a strange area.
My air is blowing cold-hot-cold-hot-cold-hot…
ANSWER : It is possible that you have a leak in the AC system. There are pressure switches that will turn off the compressor if the pressure is too high or too low. The low refrigerant level could cause the AC compressor to cycle on and off. If you would like to have this done, a certified technician from YourMechanic can come to your car’s location to diagnose the AC system and make the correct repair.
Hot air mixed with cold blows from air conditioning
ANSWER : Hey there. You will most likely have to have a mechanic bypass the heater coolant lines to have this resolved. Your A/C may not be controlling the air flow inside the evaporator correctly out of the vents and may be the blend door actuator stuck in the heat position. Have the AC system diagnosed first before bypassing the heater.
In a 2003 Cadillac CTS at idle position, it does blow hot air but once driving, I only feel cold air coming through the vents.
ANSWER : Hi there. It is possible that you have an obstruction of engine sludge or debris inside the heater core. This typically will cause elevated engine temperature and heaters to not work as well during operation; or specifically – when the heater control valve is opened during operation. It’s also possible that the heater control valve is not working as intended; which might explain the cooler air during engine operation. I would first suggest reading this article which explains some of the common symptoms of a failing heater control valve. If these are common with your issue, it’s probably best to have a professional mobile mechanic come to your location and complete a heater is not working inspection to determine the source of this issue.
When idling, car overheats and A/C blows hot air – 2001 Saturn L100
ANSWER : Hello. The most likely cause of the issue that your are having would be a faulty cooling fan. The cooling fans purpose is to keep the radiator and condenser for the air conditioning cool during the idling function of the vehicle.
If the cooling fan is not working, this will cause the radiator and condenser to get very hot. When the radiator and condenser get hot, this can cause the vehicle to overheat and the air conditioning not to work. When the vehicle is driving at higher speeds, the force of air that is created towards the vehicle will flow through the radiator and condenser and therefore keep them cool. I would recommend having the cooling fan checked to make sure that it is working properly. If not, I would recommend having the cooling fan replaced.
A question regarding my car blowing intermittently hot and cold air.
ANSWER : It sounds like you have failed cooling fans. When the car is at idle, the fans should run to pull air across the A/C condenser to regulate refrigerant temperatures and the radiator to regulate coolant temperature. If these fans fail, then these components will receive no airflow at idle, but will still get airflow while driving due to the car moving. I would suggest having a qualified technician, such as one from YourMechanic, inspect your fan operation, as well as the rest of the cooling system for proper operation.
My car heater will blow hot air and drive fine for 30 minutes then my heater blows cold air and my car overheats
ANSWER : Hello. With the recent repairs that have been made to the vehicle, there is only one main heating component that you have not looked into. This would be your heater core. The heater core is responsible for pulling hot coolant from the engine. This hot coolant runs through the heater core as the ambient air is pushed through to warm before entering the cabin. If the coolant can’t flow through the heater core, then the air will blow cold. This can be caused by a clog, a faulty switch, or a process known as electrolysis (electrical current running through coolant). Unless there is a clog that can be dislodged, these issues will all result in a new heater core. To get a precise diagnosis of the problem, I recommend having an expert inspect the overheating problem so this can be resolved.
