We all know the feeling of getting into a car that’s been parked outside on a hot day — the inside is stifling and uncomfortable. You want a quick cooldown, but is cranking the air conditioning on high blast really the best way to do it? The experts at Consumer Reports share some tips for fast, fuel-efficient car cooling.

Need to cool down your car quickly? Despite what you might think, this isn’t the time to use your car’s automatic start. That’s according to Consumer Reports’ car expert. Your car’s air conditioning works much better when you’re driving because the faster the engine turns, the faster the AC compressor runs, which lets the system cool more effectively. It is also more efficient since the engine will use less fuel.

Once you hit the road, turn on the air conditioner and open all the windows for 10 to 20 seconds. Crank the fan! Once cold air starts flowing through the vents, roll up the front windows, but keep the rear ones cracked open for another 10 to 20 seconds. This pulls cold air to the back of the car. If you have passengers in the back seat, turn off recirculation mode so the air in the back doesn’t get stale and hot.

Then, adjust the AC to the lowest temp and adjust the fan speed and direction to make you comfortable. This will make the AC unit more efficient, dry out the air more, and save some fuel.

Another tip: If you’re stuck in stop-and-go traffic on your way to the beach and have a newer car with an auto start-stop system, you may want to turn it off!

While this feature saves fuel by shutting off the engine when you’re stopped, it may also shut off the car’s AC compressor, which you’ll need to keep cool.

Just as you should check AC filters at home, Consumer Reports says you should also check your car’s cabin air filter to make sure it’s clean. A dirty filter prevents optimal airflow. Replacing them is usually inexpensive and simple to do yourself.

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