How Filters Keep Your Car Clean Under the Hood

filters under the hood

Your car has three different types of filters that work to keep the contaminants, debris, and impurities out of the fuel system, engine air supply system and car cabin air supply. They are the oil filter, air filter, and cabin air filter, respectively. If any of these filters is not functioning optimally, you will soon see that your car is not running, as it should. Thus, it is advisable to have your mechanic check them at regular intervals as recommended by the car manufacturer. Also, make sure you have them cleaned or replaced when they show clogging.

Air filter

  • What the air filter does: The air filter protects your engine from organic and inorganic debris that may enter it. These can be bugs, dirt, road debris, water or any other impurities the car might pick up on the road. The air filter also ensures that your engine gets the oxygen-rich air supply it needs to efficiently burn fuel and give you the maximum mileage per gallon of gasoline.

  • Symptoms of wear or clogging: If the air filter does not clean effectively, the engine has to work harder to burn fuel. Not only does it consume more fuel, but it also does not burn it completely. As a result, unburnt fuel makes its way out of the exhaust resulting in a black sooty smoke and even flames. You’ll also notice lower horsepower and acceleration, and lower fuel efficiency along with coughing sounds from the car engine. You might also have trouble starting up the engine because of sooty deposits on the spark plug.

  • When to change the air filter: It is advisable to replace the air filter every 10,000 to 15,000 miles or once in 12 months. However, if you live in a rural area or drive in dusty roads frequently, you might want to have it replaced every 6,000 miles.

Cabin air filter

  • What the cabin air filter does: The cabin air filter keeps the air inside the car cabin clean. It filters out dirt, dust, pollen, allergens, smoke, soot, mold spores, and other contaminants and prevents them from entering through the air-conditioning and heating vents.

  • Symptoms of wear or clogging: If the cabin air filter is not performing properly, you’ll notice a musty odor in the car and low pressure air flow from the car cabin vents. This is because of unfiltered air circulating in the cabin. You might also notice that the air-conditioning or heating is not very effective. A clogged car cabin air filter will result in your engine diverting power towards it and you’ll notice a lower horsepower.

  • When to change the cabin air filter: Consult the owner’s manual for directions on when to change the cabin air filter. Most manufacturers recommend that you change it every 12,000 to 15,000 miles or once in 12 months. Depending on the conditions in which you typically drive, you could have your mechanic check the cabin air filter every six months.

Fuel filter

  • What the fuel filter does: Essentially, the fuel filter works to protect your engine and keep it working. It cleans and filters the motor oil to remove the contaminants and metal shavings it gathers while circulating around the engine. An efficient fuel air filter can help prolong the time frame between motor oil changes. Most fuel filters come with a bypass valve that allows the motor oil to flow around the filter if it is too clogged and does not allow the free flow of oil.

  • Symptoms of wear or clogging: A worn out or clogged fuel filter will cause the engine to work harder to pump oil. This will result in lower fuel economy and slower acceleration. An insufficient motor oil supply can also cause friction in the engine’s vital parts, and overheating. Thus, your engine could stop functioning and the car could come to a complete halt.

  • When to change the fuel filter: The frequency with which you need to have the fuel filter replaced can depend on the conditions in which you drive and the kind of filter media or the membranes inside the fuel filter. Oil filters with cellulose media need replacing every 3,000 miles while those with synthetic media could need a change at every 5,000 to 7,000 miles. Oil filters with microglass media remain effective up to 10,000 miles. As an added precaution, have your mechanic check the fuel filter for clogging every time you take the car for maintenance.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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