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Car Care Advice

Car Filters Demystified: Air, Cabin, Oil, and Beyond

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Car filters might seem like small, insignificant parts, but they are crucial in keeping your vehicle running smoothly and efficiently. From ensuring your engine breathes clean air to keeping contaminants out of your oil and cabin, each filter has a vital function. 

Let’s take a closer look at 6 common filters found in your vehicle.

1. Engine Air Filters

Engine air filters maintain clean air for engine combustion, which is crucial for your vehicle. They filter out potentially harmful dust, dirt, and debris from the air before it enters the engine. These air filters are made of materials like paper, foam, or gauze; some are reusable. Each type has its advantages, but all serve the same fundamental purpose of keeping your engine clean.

Maintaining Your Engine Air Filter

If your air filter is dirty, you might notice reduced fuel efficiency, a misfiring engine, or unusual engine sounds. You should check your air filter every 12,000 – 15,000 miles or follow intervals recommended in your owner’s manual. 

2. Cabin Air Filters

Cabin air filters ensure the air inside your vehicle is clean and free from dust, pollen, and other pollutants. They contribute to a healthier and more comfortable driving experience. There are several types of cabin air filters: 

Maintaining Your Cabin Air Filter

It’s generally recommended that you replace your cabin air filter every 10,000 – 20,000 miles, or as specified by your vehicle manufacturer, but that depends on other factors. If you notice reduced airflow from your vents, unpleasant odors, or increased allergy symptoms, your cabin air filter might need a change. 

3. Oil Filters

Oil filters remove contaminants like dirt, carbon residue, and metal particles from your engine oil. This keeps your oil clean, ensuring your engine runs smoothly and preventing wear and tear.

The two main oil filter types are the primary (full-flow) filters and secondary (bypass) filters:

Maintaining Your Oil Filters

If your oil filter is clogged, you might notice decreased engine performance, dirty exhaust, or low oil pressure. You should replace your oil filter at every oil change, though intervals will depend on your vehicle and oil type. 

4. Fuel Filters

Fuel filters remove impurities and debris from the fuel before it reaches the engine. This ensures that only clean fuel is used in combustion, which helps maintain optimal engine performance.

There are two main types: inline filters and cartridge filters:

Both fuel filters screen contaminants before the fuel reaches the engine. 

Maintaining Your Fuel Filter

 A dirty fuel filter can cause engine misfires, stalling, difficulty starting, and reduced engine performance. These issues indicate that it’s time for a filter change. Otherwise, fuel filters typically last between 20,000 – 150,000 miles. Since that’s a wide range, following the change intervals recommended in your vehicle’s owner’s manual is best.

5. Transmission Filters

Like the oil filter, the transmission filter keeps your transmission fluid clean by filtering out contaminants and debris. This helps ensure smooth gear shifts and prolongs the life of your transmission system.

Maintaining Your Transmission Filter

Check your vehicle’s manual for recommended replacement intervals, typically every 30,000 miles. If your transmission filter is clogged, you might experience transmission slipping, hard shifting, or unusual noises from the transmission area. These symptoms indicate that it might be time for a filter replacement.

6. PCV (Positive Crankcase Ventilation) Valves

The PCV valve isn’t a filter per se, but it works to recycle the toxic gasses produced during the combustion process of your car engine. In doing so, it protects the engine, the environment, the oil, and your car’s crankcase.

Maintaining Your PCV Valve

Poor engine performance, increased oil consumption, and oil leaks are signs of a faulty PCV valve. If you notice these issues, it may be time to check your PCV valve. There isn’t a set interval for replacing it, but you should have it inspected and cleaned every 20,000 – 50,000 miles.