My air conditioner blows warm when idle, looses coolant and starts to overheat.

My explorer started blowing warm air when idling. A week later, it was blowing warm air at high speeds and the engine got all the way hot. So I checked it out and the coolant and the oil was low. I filled up the coolant and added oil, and the next day had an oil change and the ac worked fine for a week. Well it started back. It hasn't got hot on me yet and the oil is fine but ac blowing warm while idling and i'm loosing coolant. When I got out of it today after driving awhile, the coolant was bubbling out from the overflow cap. What is causing this? The fan has resistance when trying t
Experienced mechanics share their insights in answering this question :
Hi! I have a couple of thoughts that may help you sort out the issues with your Explorer. There may be separate root causes of the issues with the air conditioning system and the cooling system.

The first thing I would do is a pressure test on the cooling system. This will help to identify whether there are any leaks in the cooling system.

Something as simple as a faulty radiator cap can allow coolant to bubble over out of the radiator. I would just put a new radiator cap on it.

Your engine may actually have a blown head gasket. One of the symptoms can be engine compression leaking into the cooling system and over-pressurizing it to the point of pushing coolant past the radiator cap and out of the overflow. There is a testing tool that can can be helpful called a block tester. It is used to identify the presence of combustion gasses in the cooling system.

A qualified technician from YourMechanic can come to your home or office to inspect your AC system and recommend the best path to repair.

How to Identify and Fix Common car Problems ?

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

One of the most common reasons why your engine overheats when your AC is on is a faulty engine cooling fan, fan switch, or fan motor. A bad engine coolant sensor, an overloaded AC compressor, a broken water pump, and blocked AC condenser fins can also create overheating issues.
If your A/C flip-flops from hot to cold and back again, your expansion valve could be failing. The expansion valve removes pressure from liquid refrigerant to allow expansion from a liquid to a vapor state in the evaporator. If the valve is blocked, the refrigerant flow could be restricted or could be too unrestricted.
Why is my Explorer A/C blowing hot air? If your car`s air conditioning isn`t blowing cold air at all (or it tries, then turns warm), you could have a clogged expansion valve, a faulty compressor clutch, a leak, or a malfunctioning fuse in the system. How does my A/C system get a leak?
One of the most common reasons your car AC is blowing hot air is because of a refrigerant issue—specifically, a loss of refrigerant. This loss of refrigerant can occur either due to a leak or because your car`s refrigerant levels are too low.
One common reason engines overheat while idling is a faulty or broken cooling system. This could include problems with the radiator, water pump, or fan belt. If any part of your car`s cooling system is not functioning properly, your engine may be at risk of overheating.
Why does my car overheat when the ac is on? Your car is overheating likely due to AC compressor overload, issues with the radiator, defective engine coolant sensor, a faulty fan, faulty cooling system, or faulty in-vehicle components.
Why Does Your Car AC Get Warm At Idle? The reason your car`s A/C may become warm when idling is that the flow of refrigerant slows down, which affects its cooling ability. The cooling fan may also not be getting enough airflow when the vehicle is stationary, leading to the same issue.
What`s making my Explorer A/C put out warm air? If your car`s air conditioning isn`t blowing cold air at all (or it tries, then turns warm), you could have a clogged expansion valve, a faulty compressor clutch, a leak, or a malfunctioning fuse in the system.
Your engine could overheat.

Coolant helps pull heat away from the engine. So, without enough coolant, the engine could overheat or seize up. Continued use of an overheated engine could lead to permanent damage, such as pistons welding to the cylinders.

Running an engine without the thermostat can cause the engine to overheat due to the coolant passes through the engine too fast and will not let the coolant absorb the heat from the engine.
Another symptom that may present itself when the fan has failed is the vehicle overheating while the engine is idling with the AC on. During the conversion process, the AC condenser is able to generate a considerable amount of heat, which can affect the overall engine temperature enough to cause overheating.
The air conditioner can cause an engine to overheat quickly because it makes the engine work harder. Even though it`s hot outside, if you turn off the AC, you may be able to avoid overheating, especially if you take the next step, which we apologize for in advance.
Turn Off the Air Conditioner

It may seem counterintuitive, but when you`re trying to prevent overheating, it may help to turn off your car`s air conditioner. The energy required to power the AC can overload your engine. Then, it can exacerbate an overheating problem.

Every time it cycles on it creates more strain on the engine, generating heat. In addition, the engine`s serpentine belt drives the AC compressor, which also takes more energy from the engine. So yes, running your air conditioner during hot weather will cause the engine to run hotter.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My air conditioner blows warm when idle, looses coolant and starts to overheat.
ANSWER : Hi! I have a couple of thoughts that may help you sort out the issues with your Explorer. There may be separate root causes of the issues with the air conditioning system and the cooling system.

The first thing I would do is a pressure test on the cooling system. This will help to identify whether there are any leaks in the cooling system.

Something as simple as a faulty radiator cap can allow coolant to bubble over out of the radiator. I would just put a new radiator cap on it.

Your engine may actually have a blown head gasket. One of the symptoms can be engine compression leaking into the cooling system and over-pressurizing it to the point of pushing coolant past the radiator cap and out of the overflow. There is a testing tool that can can be helpful called a block tester. It is used to identify the presence of combustion gasses in the cooling system.

A qualified technician from YourMechanic can come to your home or office to inspect your AC system and recommend the best path to repair.

Air conditioner blowing warm air. Heat blowing warm air. Neither hot or cold
ANSWER : If the A/C system is full and pressures are reading correctly, and the cooling system is in proper working order (thermostat opens, no overheating, etc.), then most likely the problem lies with the dash. The climate control head unit may be at fault. One or more blend doors behind the dash may be stuck or broken. If you’re unable to fix this issue yourself, consider YourMechanic, as one of our mobile technician can come diagnose the issue with your A/C firsthand and help you fix it accordingly.

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.

air conditioner started making loud screeching noise and started only blowing hot air, then the noise stopped but still only blows
ANSWER : The noise is possibly from a failed compressor clutch or the compressor itself is faulty. Another possibility is the pulley bearing on the front of the compressor has failed. The issue should be fairly evident to the inspecting mechanic after some simple tests. To resolve this, the recommended diagnostic is an a/c system inspection. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

My 2003 Hyundai air conditioning works fine but often starts blowing hot air, especially when idling.
ANSWER : Hi There,
It sounds like you may have a condenser fan that may not be cooling the AC condenser properly. As you may know, the job of the AC condenser fan is to cool down the AC condenser as it generates a lot of heat during the course of its primary function, which is to convert the AC gas refrigerant into a liquid form, a process that generates a significant amount of heat. As the AC condenser fan blows cool air across the condenser, this allows the condenser to remain cool, keeping the pressure down in the AC system which helps to generate cooler air. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle.

everytime I turn my car on the ac starts to blow air even if I switch it off. it won’t blow cold air or heat.
ANSWER : Hi there. Based on your question and input, it looks like your AC control switches are damaged, causing the vents to activate even if the switch is not activated. This is sometimes an electrical problem, as it could be triggered by a damaged electrical relay. You might want to have a professional mechanic complete an AC is not working inspection, so they can determine what is causing this issue you’re experiencing and recommend the right repair.

air conditioner not blowing air from dash vents, but blowing air from side vents
ANSWER : A few different items can cause the air to not blow out of the dash vents. The most common are a blend door or a control switch. The best method for the AC diagnosis feature can be found in the vehicles owners manual. I recommend having your AC checked by a qualified technician, such as one from YourMechanic, to have the problem diagnosed and repaired correctly.

No coolant in the reservoir. Seen low coolant message. I added 2 quarts of 50/50 coolant. Still getting the message. How much coolant doe it need?
ANSWER : Hi there. For the coolant light to go out, you would need to have the coolant between the low line and the full line for the light to go out. If the coolant is low and keeps on being low, then look for any signs of coolant leaks. You may have to use a coolant pressure tester to pressurize the reservoir to allow the leak to be found.

If you need further assistance with the coolant being low and the warning light being on, then seek out a professional, such as one from Your Mechanic, to help you.