Tech Tip: Cabin Air Filter Q & A – UnderhoodService

Tech Tip: Cabin Air Filter Q & A

How do you replace a cabin air filter? First you have to find it. The cabin air filter is usually located behind the glove box or at the base of the windshield in the cowl area over the HVAC inlet duct. The exact location can be found in the vehicle owner's manual or a filter reference guide. On most Fords, the filter is located under the ....

Question: How do you replace a cabin air filter?

Answer: First you have to find it. The cabin air filter is usually located behind the glove box or at the base of the windshield in the cowl area over the HVAC inlet duct. The exact location can be found in the vehicle owner’s manual or a filter reference guide.

On most Fords, the filter is located under the hood in the cowl area. On Chrysler models, it is located under the dash. On GM products, it might be under the hood (Impala, Lumina and Monte Carlo), under the dash (Avalanche, Silverado, Suburban and Tahoe) or behind the glove box (Venture). On Toyota, Lexus, Nissan and most Honda models, you’ll find the filter behind the glove box.

On vehicles where the cabin air filter is mounted under the cowl at the base of the windshield, some disassembly may be required to replace the filter. This may involve removing a plastic cowl cover. The area around the filter usually collects debris, so this area should be cleaned to remove any leaves, bugs or other debris before the old filter is pulled out. This will prevent any contaminants from falling into the HVAC inlet duct.

On vehicles where the filter is located behind the glove box, the glove box may have to be removed to replace the filter. On others, the filter can be accessed from under the dash and pulled out of a slot in the HVAC unit.

Most cabin air filters are flat-panel filters, but some have unusual shapes, so they will fit the HVAC inlet duct. Some filters also come in two sections to make replacement easier.

Q. How often should a cabin air filter be changed?

A. As often as necessary to prevent the filter from clogging, or in the case of cabin air filters that also absorb odors in addition to blocking dust, as often as needed to keep unpleasant odors to a minimum.

Under “normal” driving conditions for a vehicle driven primarily in a city or suburban area, or on paved highways, the average service life of a typical cabin air dust filter is about two to three years, or 25,000 to 30,000 miles. For a vehicle in a rural area that is driven frequently on gravel roads, the service life of the filter may only be six months or less.

Cabin air filters are very efficient and have electrostatically charged fibers that can trap particles smaller than 1 micron in size. Most quality cabin air filters will stop 100% of all particles that are 3 microns or larger in size and 95-99% of particles in the 1-3 micron size range. This prevents most pollens, mold spores and bacteria from entering the vehicle. Some cabin air filters are also treated with a chemical biocide to inhibit the growth of odor-causing bacteria, fungi and algae.

When a cabin air dust filter becomes clogged, it restricts airflow into the HVAC unit. This may cause reduced airflow and cooling from the air conditioner and/or lower heater/defroster output during cold weather.

If the cabin air filter is a combination type that has a layer of activated charcoal to absorb exhaust fumes and other unpleasant odors, the service life of the odor filter is only about a year, or 12,000-15,000 miles of normal driving. So when odors start to become more noticeable while driving (and they aren’t coming from leftover pizza or dirty socks in the back seat), it is probably time to replace the filter.

Q: How much time does it take to replace a CAF?

A: Depending on the vehicle, replacement times are usually around 25-40 minutes, depending on location of the filter and housing removal.

According to ATP’s Interior Ventilation Filter Catalog, the BMW 3 Series has an approximate installation time at 45 minutes due to the removal of front dash panels.

On the other hand, CAF replacement for the BMW X5 is only about 10 minutes, since the filter is located in the center of the cowl under the hood.

You May Also Like

Autoshop Solutions Partners With Turnkey Marketing

Both companies only focus on the automotive aftermarket and have the same goal of keeping those bays full.

Autoshop Solutions has partnered with Turnkey Marketing to offer a comprehensive marketing solution for all shops. With this partnership, Autoshop Solutions and Turnkey Marketing can now provide an even more powerful marketing program for their customers. Both companies only focus on the automotive aftermarket and have the same goal of keeping those bays full! "Turnkey Marketing and Autoshop Solutions have partnered together to help auto repair shops have a complete marketing strategy and excellent implementation," said Carrie-Lynn Rodenberg, founder of Turnkey Marketing. “We partnered with Autoshop Solutions because they are a leader in automotive aftermarket digital marketing and truly want what’s best for their clients.”"We are very excited to work with Carrie-Lynn and her entire team at Turnkey Marketing," stated Margaret Palango, CEO, Autoshop Solutions. "With the combined efforts of their marketing guidance and our digital services we can now offer a robust and comprehensive marketing package.”

AP Emissions Releases January New Part Number Update

The release includes direct fit EPA converters covering more than 6.6 million vehicles in operation.

Determining Catalytic Converter Efficiency

Almost every part on the engine determines how long a catalytic converter will last.

Domestic Gasoline Engine Oil Specifications

If it’s been more than a year since last oil change, the IOLM will display a reminder message, regardless of mileage.

Curing Intermittent And Chronic Fuel Pump Failures

The fuel pump may be one of the most misdiagnosed components on a vehicle.

Other Posts

Jump Starting an EV

If an EV with a full battery won’t start, here’s how you can get it up and running.

Auxiliary Water Pump Diagnostics

A car or truck comes into your shop with a complaint of poor heater performance- the issue may be the auxiliary water pump.

Do You Know The Cause Of A No-Spark Condition?

A no-spark condition could be the result of communication errors or missing data from a dead module.

Belt-In-Oil Timing Systems

Oil contamination of the belt drive has been a death sentence, due to the rubber and fiber construction of the belt.