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Q: Having problem with ouside air coming into the A/C

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We are having a problem with our A/C in the car. We are thinking about taking it to the mechanic. The issue is that we're getting random whiffs of outside air, as if the recirculation isn't fully working. When we're driving, the air seems to be super cool and dry like normal. So it isn't a problem until we get behind a vehicle with lots of exhaust or anything with a strong smell.

Also, when we're stopped at a light or idling, the air gets slightly more humid than usual. We haven't replaced the cabin filter recently. Could that be it? Or something else?

Since the A/C compressor is driven off the engine crankshaft, the A/C will typically work better at higher RPMs. What you’re experiencing may be normal for your vehicle, or you may need an A/C system recharge to restore peak A/C performance.

Replacing the cabin filter is a good first step towards eliminating any offensive odors. Once again, being able to detect some outside odors may be normal for your vehicle. If the odors are excessive, suspect a problem with the blend door or its control system.

The best way to get to the bottom of these issues it to have your vehicle’s A/C system inspected by a professional, such as one from YourMechanic.

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