Why is my air system blowing out hot air in spurts and why is the temperature gauge nearing hot while in use?
My service light comes on and stays on. When the cool air system is in use it sometimes blows out hot air. Also the temperature gauge nears the hot zone when the cool air system is in use. It hasn't reached the hot zone yet but it has come pretty close. I haven't used the air cooling system since Monday and the temperature gauge has stayed at normal levels. I had some coolant added on last Thursday and when I checked it on Monday there was none in the the reservoir at all.
My car has an automatic transmission.
My car has an automatic transmission.
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This can be caused for a variety of reasons such as a malfunctioning thermostat, a radiator not flowing properly, a faulty coolant temp sensor or AC refrigerant not properly being supplied to the AC compressor. Your car’s AC system puts a heavy strain on your car’s engine when it runs as it requires a lot of power to run. When the AC compressor comes on it puts additional strain on the motor that may be already struggling to stay cool as a result of any of the issues named above. I would recommend having an expert from YourMechanic come to your home to diagnose and repair.
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Another symptom of a bad or failing ambient temperature sensor is inconsistent cooling. As the ambient temperature sensor plays a direct role in the automated function of the AC system, when it is having a problem this may interfere with the system`s ability to cool the vehicle.
When the temp shows “cold” the AC will not cycle on; that`s normal. The issue is in the temp sensor circuit. The fans running is because the ecm does not see a temp sensor so it assumes a hot condition. If battery disconnect solves the problem it is resetting the ecm (engine control module; i.e. computer).
The thermostat sensor is located near the evaporator coils. These coils are inside your air conditioner unit. As the air is sucked through the return vents, the air passes by the sensor and the coils. As the air passes the sensor, it reads the temperature and compares that reading to the setting on your thermostat.
Faulty cooling fan – A faulty cooling fan, cooling motor, or any connectors` controls that activate the cooling fan could also be the cause of your car overheating when idle and the AC is turned on.
Signs of a Faulty Sensor
You might notice that your air conditioner doesn`t turn off when the house reaches the set temperature if you have a faulty sensor, Your AC will just continue to blow cold air. The temperature may even become uncomfortably cold.
If you notice that your engine overheats, the coolant temperature sensor could be the problem. At times, the coolant temperature switch may fail such that it starts transmitting hot signals permanently. This causes the computer to erroneously counterbalance the signal, thereby causing the engine to misfire or overheat.
Look online for the hot and cold readings of your vehicle`s temperature sensor — or check the car`s manual — and compare your readings to see if they closely match. If they do, your sensor is functioning properly and you may have an issue elsewhere. If not, you`ll need to replace your sensor.
Also known as an air conditioning sensor, a thermostat sensor is a component in central AC systems that is designed to measure the ambient air temperature. It works in conjunction with a thermostat to provide control over your home`s indoor temperature.
A temperature sensor can help if you`re consistently too cold or too warm in a room in your home. A thermostat only measures the temperature in the room that it`s in. It heats or cools your entire home based on that temperature, even if it`s different from the rooms where you spend the most time.
Car overheats when driving but not when idling
If your temperature gauge is fine until you make the car work, the most likely issue is coolant flow.
Can a Bad AC Compressor Cause My Car to Overheat? The compressor itself cannot cause the vehicle to get overheated. However, if the compressor clutch is engaged but the compressor is dragging to function properly, the extra strain on the engine can cause your car to overheat.
The calibration screw is inside a piece of metal in the thermostat. Using the proper size screwdriver, you can turn the screw to open the contacts. After a few seconds, turn the screw to close the contacts. This will reset the contacts to provide a good connection.
A coolant temperature sensor (CTS) (also known as an ECT sensor or ECTS (engine coolant temperature sensor) is used to measure the temperature of the coolant/antifreeze mix in the cooling system, giving an indication of how much heat the engine is giving off.
A failing oxygen sensor is an oft-overlooked cause of overheating. Your converter links to oxygen sensors in your vehicle. These sensors are used to measure the mix of air and liquid fuel. If the mix is off and becomes too rich, your catalytic converter can overheat as a result.
The Freon is Leaking
Freon, or coolant, is the chemical in the air conditioning system that cools the air. If the system is leaking, then this chemical will eventually run out. Today`s A/C systems are more sensitive than the older ones. The air conditioner will not work properly if there is not enough of this chemical.
Traditional air conditioner uses a temperature sensor installed on the evaporator of indoor unit for feedback control.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Why is my air system blowing out hot air in spurts and why is the temperature gauge nearing hot while in use?
ANSWER : This can be caused for a variety of reasons such as a malfunctioning thermostat, a radiator not flowing properly, a faulty coolant temp sensor or AC refrigerant not properly being supplied to the AC compressor. Your car’s AC system puts a heavy strain on your car’s engine when it runs as it requires a lot of power to run. When the AC compressor comes on it puts additional strain on the motor that may be already struggling to stay cool as a result of any of the issues named above. I would recommend having an expert from YourMechanic come to your home to diagnose and repair.
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.
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.
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 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.
My car’s air conditioning/heating system only works for a brief time and blows the wrong temperature air
ANSWER : Your Villager comes equipped with either an automatic climate control system or a manual controlled climate system. The automatic controlled system uses four separate sensors and as many modules to operate. Any of these can be the source of the symptoms you are experiencing.
With your symptoms, I tend to think you have an automatic system. If this is the case, you will need a shop level scanner to access the vehicle climate control data. Without access to this data, repairing your system will be guessing.
When it comes to a manual system, it only changes in that there aren’t any sensors to allow the computer to determine what to do. The diagnosis is virtually the same. When it comes to the blower motor tuning off after ten or so minutes, this is most likely the same component that is causing the temperature settings to be incorrect.
Because of the complicated nature of these systems, I recommend having a professional mechanic, such as one from YourMechanic, perform an inspection in order to diagnose the precise nature of the AC/heating problem.
Air conditioner blows hot air. 1995 Mercedes-Benz E300
ANSWER : Hi there, thanks for writing in about your 1995 Mercedes-Benz E550. This could be a variety of issues, such as no pressure or low refrigerant levels, a bad compressor clutch, or a compressor not engaging correctly. Check to see if the cooling fans are on when the AC is running. Most systems are designed to have them run when the AC is on. Also, check to be sure the compressor is engaged. Look to see if the pulley is spinning when the car is running with the AC on. If you need help with this, a qualified professional from YourMechanic can come to your car’s location to inspect the AC system and pinpoint the necessary repair.
There was a temperature change in my car.
ANSWER : Hi there. The thermostat on the air conditioning is not functioning correctly. I recommend replacing the thermostat temperature scanner for your air conditioning system. The thermostat will determine when the blend doors are to activate and when the air conditioning clutch is to engage. If you need further assistance with your air conditioning system, then seek out a professional, such as one from Your Mechanic, to help you.
