Skip the auto shop - Our mechanics make house calls

Q: Trying to stop outside air from coming into my car

asked by on

How do I prevent outside fumes (from other cars) from coming in through the air conditioning/heater vents? The owner's manual says to put the A/C on Max A/C, but that doesn't work. Most other vehicles have a button that shuts off outside air, but my car doesn't. Any tips?

A: The Max A/C setting should close the fresh ...

The Max A/C setting should close the fresh air vents off, preventing fresh air from entering the climate control system, but there is natural ventilation built in every vehicle so it is impossible to completely seal the vehicle from outside air. If the Max A/C setting does not close off the fresh air vents, then the function of the fresh air flaps need to be checked. A professional mechanic will be able to do this for you and diagnose the problem with your A/C system accurately.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Vehicle overheating

Hello. There are several different parts of your cooling system that could cause your car to overheat. A bad water pump, radiator, faulty thermostat, clogged heater core, or leaking or clasping cooling hoses could cause this issue. The worst case...

Q: where do i find the ac control module and what it looks like.

Hello. If the car needs the HVAC control module that is the control panel itself. It contains the entire computer unit as one unit. I usually test the power supply to the module first and the ground. It is common...

Q: My car idles rough when at a stop and almost stalls why might this be?

Hello. Typically, if this vehicle runs fine at all other times and will have trouble idling when coming to a stop, it is almost always caused by a bad idle control valve. Most of the time the valve fails making...

Related articles

How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...