Face masks have become the symbol of the pandemic era – a visual metaphor for the tiny, unseen viral foe that could be lurking around any corner. Some opt for a scarf wrapped around their face, others make do with a t-shirt yanked up over their mouth. The more creative hook colourful homemade varieties around their ears, while a lucky few wear distinctive surgical masks or, rarer still, N95 respirators. 
While a few months ago anyone wearing a mask in public would have drawn stares in many countries unaccustomed to this behaviour, they are now a reminder of the strange times we live in. Where am I going with this? Well, a mask is essentially a filter. It's filters out unwanted contaminants in the air around us, much as the air filters do in a vehicle. In our case, we trying to keep the germs out and prevent ourselves from falling sick. In our vehicles, the “germs” are dust, leaves and dirt, which ruin our engines’ health. 
Which brings me to the two of the most important air filters in your vehicle, the air filter in your engine and your cabin air filter housed in your air conditioning unit. 
As most of us have by now discovered, it is not easy to breathe through a face mask. The thicker the material, the harder we must work to inhale through it. In a similar vein, the filters in your vehicle become clogged over time. And the more clogged the filter becomes, the harder the engine or air-conditioning compressor must work to maintain the airflow. 

The Engine Air Filter:

 

A car engine combines fuel and air in the combustion chamber to create power. This air reaches the engine through an air filter that works to keep out road debris, dirt, bugs, and other contaminants that can damage the engine. At the same time, the air filter must allow enough air to reach the engine so it can perform effectively. 

 

Over time, the air filter can become dirty and clogged, and the lack of air can affect the overall performance of your car.

 

When To Replace the Engine Air Filter: 

 

Most vehicle manufacturers recommend that you change the air filter every 15,000 to 30 000kms, or every 12 months. However, there are some caveats. If you live in rural areas and typically drive on dusty sand roads – you may need to replace it sooner. Similarly, if you drive predominantly in crowded areas where there is heavy traffic - causing you to stop and start more often also requires you to replace the air filter more frequently. 

 

Should you fail to replace your air filter at the suggested intervals, you may notice distinct signs of it needing replacement. 

 

8 Signs Your Air Filter Needs Replacing 

 

1. Reduced Fuel Economy

Your engine compensates for lower amounts of oxygen by consuming more fuel to produce sufficient power. Thus, if you notice your fuel consumption worsening, it could indicate that the air filter needs replacing. However, this is true only for carburetted cars, most of which were made before 1980. Carburettors mix air and fuel at the ideal ratio for the internal combustion engine. Newer cars with fuel-injected engines use onboard computers to calculate the amount of air taken into the engine and adjusts the fuel flow accordingly. Therefore, the cleanliness of the air filter on newer cars should not significantly affect fuel economy. 

 

2. Misfiring Engine

Restricted air supply from a dirty air filter results in unburnt fuel exiting the engine in the form of soot residue. This soot accumulates on the spark plug, which in turn cannot deliver the necessary spark to combust the air-fuel mixture. You will notice the engine does not start up easily, misfires, or jerks roughly as a result. 

 

3. Unusual Engine Sounds 

In normal circumstances, when your car is stationary with the engine turned on, you should sense the smooth rotation of the engine in the form of subtle vibrations. If you notice your car vibrating excessively or hear coughing or popping noises, it is often from a clogged air filter causing dirtying or damaging a spark plug. 

 

 4. Check Engine Light Comes On. 

Many modern engines suck up about 10,000 gallons of air for every single gallon of fuel burned in the combustion cycle. The inadequate air supply can result in carbon deposits — the by-product of combustion — accumulating in the engine and setting off the Check Engine Light. If that happens, have your mechanic check the air filter among other diagnostics. The Check Engine light can illuminate for a variety of reasons. A mechanic will need to scan the onboard computer for the stored trouble code that triggered the Check Engine Light as well as the source of the problem. 

5. Air Filter Appears Dirty. 

A clean air filter appears white or off-white in colour, but as it accumulates dust and dirt, it will look darker in colour. However, very often, the inner layers of filter paper inside the air filter might have dust and debris that is not visible even in bright light. This makes it essential that you have your mechanic check the air filter when you take the car in for maintenance. Make sure to follow the manufacturer’s instructions regarding replacement. 

 

6. Reduced Power

If your car does not respond adequately or if you notice jerking movements when you press the accelerator, this could indicate that your engine is not receiving all the air it needs to perform. Since it improves airflow, replacing your air filter can improve acceleration or horsepower by up to 11%. 

 

7. Black, Sooty Smoke or Flames Exiting the Exhaust

The inadequate air supply can result in some of the fuel not burning completely in the combustion cycle. This unburnt fuel then exits the car through the exhaust pipe. If you see black smoke coming from your exhaust pipe, have your mechanic replace or clean the air filter. You might also hear popping sounds or see a flame at the end of the exhaust caused by heat in the exhaust system igniting the unburnt fuel near the tailpipe. This is a potentially hazardous condition and needs to be diagnosed right away. 

 

8. Smell of fuel when Starting the Car 

If there is not enough oxygen entering the carburettor or fuel ejection system when you start the car, the excess unburnt fuel exits the car through the exhaust pipe. Instead of seeing smoke or flames coming out of the exhaust pipe, you will smell fuel. This is a clear indication that it’s time to replace the air filter. 

 

Replacing your air filter benefits car longevity and engine performance. Engine air filters prevent harmful debris from damaging crucial components to keep the car running smoothly. They contribute to efficient driving by helping maintain the right air-to-fuel ratio, preventing the excess fuel consumption. Dirty air filters keep the system from getting the right amount of air or fuel and make it harder for the engine to perform its role. Having a fully functioning engine air filter is critical to optimal car operation. 

 

Visit www.startmycar.co.za to find the correct air filter for your vehicle.

 

The Cabin Air Filter

 

The cabin air filter is the filter responsible for filtering the air that is fed into the vehicle’s heating and air conditioning systems. The filter traps dust, pollen, and other foreign particles, preventing them from entering the vehicle and polluting the cabin. Since they work in essentially the same fashion as a regular engine air filter, cabin air filters get dirty and should be replaced when they become excessively contaminated, or at the regular service interval recommended by the manufacturer. 

 

Usually a dirty cabin air filter will produce a few symptoms that can notify the driver that attention may be required. 

 

1. Poor air flow

The most common symptom associated with a bad cabin air filter is poor air flow from the vehicle’s interior vents. An excessively contaminated cabin air filter will not be able to filter the incoming air as effectively as a clean filter would. As a result, this will cause restricted air flow for the AC system. Additionally, this will cause the vents to blow with noticeably less force, reducing the overall cooling capacity of the AC system, and will also place an additional strain on the AC blower motor. 

 

2. Unusual odour from the vents

Another symptom of a bad or failing cabin air filter is an unusual odour coming from the vehicle’s interior vents. An excessively contaminated filter may produce a dusty, dirty, or musty smell. The smell may become more pronounced when the air is turned on and may make the cabin uncomfortable for the passengers. 

 

A cabin filter is a simple component that should be replaced when necessary to keep the AC system working as efficiently as possible, and to keep the cabin as comfortable as possible for the passengers. I recently replaced my cabin filter, and I can now run my aircon on speed 2 instead of speed 4 and get the equivalent air flow. Startmycar stocks a comprehensive range of cabin filters, starting from as low as R90. Its also a part you should be able to fit at home, in under ten minutes. Simple Google or Youtube “How to replace a cabin/aircon filter on {insert your car make and model here}”.