Hot air when driving and cold when idling probably means you have a vacuum leak somewhere and the vents are going to “defrost” instead of “people” (it’s probably still cold, just not aimed at you). If it was reversed (cold when driving, hot when idling), you need to check your fans and your refrigerant.
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Why does the AC in my car only work when I’m driving?
While you’re driving, the compressor spins faster so the high pressure side becomes more pressured and the low pressure side loses some pressure. This means more expansion and more cooling.
Why does my car air conditioner get warm when I stop?
Since the AC compressor is driven by the engine, it doesn’t pump as much refrigerant when you’re at a stop or driving slowly. If the system is low on refrigerant, it will show up as AC blows warm at idle and blows colder when the engine is running at higher RPMs.
Why does my AC only get cold when I accelerating?
It sounds like the air compressor or condenser are on the same belt as the main pulley. This could mean that there is some slipping on the belt and when you accelerate, it activates something called a tensioner which helps keep the belt taut, thus making the car blow cold air.
Why does my heat not work when idling?
Two things come to mind, defective or wrong thermostat or low coolant level. The engine makes very little heat when idling, and if the thermostat does not close, the engine coolant temperature may drop low enough that you’ll get no heat from the heater core.
Why does my car idle better with the AC on?
The reason the A/C or heater will smooth out idle is the ECM gets a signal when they are active and will adjust the idle to compensate for the added load.
Why does my car AC stop blowing cold air when I stop?
When the car is moving, versus stopped, there is more air flow over the condenser (the heat exchanger in front of the radiator) and that airflow is essential to system operation. To maintain airflow when the car is in stop and go traffic, or is completely stopped, condenser fans will come on automatically.
Can a dirty air filter cause car AC not to cool?
While not all vehicles are equipped with cabin air filters, those that do have them need a clean, unobstructed surface to allow air to move through freely. … A dirty air filter can certainly impede your air conditioner’s ability to cool and after time could cause unnecessary strain on the entire system.
Is it OK to run AC while parked?
As long the Car engine is running the compressor is working and the batteries are getting charged so you can keep the AC ON continuously even when when parked. Don’t put the AC ON when the car engine is OFF.
How do you unclog a heater core?
How do I know if my thermostat is stuck open?
Symptoms of a bad thermostat
Thermostat stuck open: When the thermostat is stuck open, the engine temperature drops below normal when driving, especially on the highway in cold weather. A stuck-open thermostat can also cause lack of heat from the heating system. The Check Engine light may come on too.
Why does my RPM go up and down while AC is on?
Bad Belt: One often overlooked cause of a car surging with the AC on is actually a worn compressor belt. If the belt is stretched or worn smooth, it can slip during operation. … Overfilled AC System: While low refrigerant can cause problems with your AC and engine surging, an overfilled system can cause the same problem.
Why does my car accelerate slower with the AC on?
What is happening is, basically, the air conditioner system needs extra power to run and that power is coming from your engine. With less power to work with, it means your engine isn’t able to put everything it has into accelerating – thus you often have a slower or sluggish acceleration.
How can I make my car AC colder again?
How do I check the Freon in my car?
How do I know if my car AC is working properly?
What sound does a bad AC compressor make?
So if you turn on your AC and hear a rattle, it may mean you have a failing or bad: AC compressor. Rattling or your car air conditioner making loud humming noises which get worse as you accelerate can both be signs you need to replace your AC compressor.
Will a bad AC compressor affect the engine?
Will a bad AC compressor affect the engine? A bad compressor could affect the engine in your car. If your compressor’s pulley bearing goes bad, your engine can stall due to the stuck compressor or the serpentine belt may break affecting all the accessories moved by the serpentine belt.
Why is AC running but not cooling?
If your air conditioner will turn on, and your thermostat is set properly, but your system is not cooling you may have a dirty or blocked air condenser. … If your air conditioner is still not cooling air, you may have a problem with your compressor or refrigerant and will need to contact a professional.
Is no air filter better than a dirty one?
Do not run the system with no filter. All the dust and pollen will cling to the coil in the exchange. That will be very expensive to repair. … A dirty filter is healthier than no air filter cleaner 100% an unclean filter remains a filter and can protect your engine internally all the time it’s in place.
Does AutoZone replace cabin air filters?
For the best results, your air filter should be replaced about every year or 12,000 miles, and you can make that change easily with a little help from AutoZone. … We have every cabin filter product you need, including air filters, air filter boxes, breather caps and breather filters.
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