Air filter replacement

Timely replacement of the air filter ensures normal operation of the internal combustion engine. This applies to internal combustion engines using both petrol and diesel fuel. The point is that in order to burn one liter of fuel, the power unit needs up to 15 liters of atmospheric air (the volume depends on the engine power, fuel used, including its quality, state of the ignition system, etc.). Therefore, the filter should not only perform its direct air purification work, but also not prevent it from entering the fuel path. This is a key fact in determining the need and timeliness of the engine air filter replacement.
This is done primarily through clear maintenance regulations with a frequency of 15 … 20,000 km. And independently at home. The only exceptions are new cars which during the run-in period are serviced exclusively at an official service station.
Signs of air filter clogging

Despite the fact that there are different filters and they are installed on different engines, the signs of their clogging are almost the same.
- Reduced engine power (lower thrust).
- Decrease in the dynamic characteristics of the machine (it is weakly accelerating with increasing engine speed).
- Increase in fuel consumption.
- Activation of the Check Engine bulb, which can be caused by both a direct error indicating filter clogging, and a violation of the fuel-air mixture (its significant enrichment with fuel, error P0172).
- Significant concentration of toxic substances in exhaust fumes.
In some cases, if the air filter is contaminated, there may be increased humming of the engine.
However, the above mentioned factors may be signs of other malfunctions, but it is desirable to perform the filter check as well, moreover, it is not difficult and short time to do it.
Why is it necessary to replace the air filter
There are several typical reasons why it is necessary to change the engine air filter. Among them:
- Scheduled replacement. Each car manufacturer individually indicates the mileage or time it takes to change the vehicle’s air filter. Usually the corresponding mileage is within 15…20 thousand kilometers.
- Unscheduled pollution. This can be caused by either poor quality filter material used in the device, or a long drive in contaminated air conditions (dusty conditions such as sand, dirt, etc.).
- Mechanical damage. It can be caused by improper installation, an emergency situation in the engine (in the duct), a large particle hitting the filter, which caused the filter material to fail, damage to the filter during other repair work.
Regardless of what exactly caused the failure of the device, replacement of the internal combustion engine air filter will first of all eliminate the troubles described above and also prevent their possible appearance in the future.
Constant ride on enriched mixture reduces engine life (due to the fact that the dust in the cylinders acts as an abrasive material). Therefore, timely replacement of the air filter is not only a repair, but also a preventive measure that allows to operate the machine engine in normal mode.
Frequency of replacement
Before proceeding to general considerations, it is necessary to indicate that the exact frequency of air filter replacement can be found in the manual or in the technical documentation for your vehicle. In addition, there are a number of other objective factors that affect the values mentioned. Among them are operating conditions, the use of different filters, as well as differences in engine type – for gasoline and diesel engines they are different.
For cars with an injector, for diesel engines, and especially for diesel engines with turbocharger, mileage for an air filter to replace after how long it should be done is reduced by 20 … 30%, for diesel engines with a turbine even by 50%.
In most cases, on gasoline engines, the air filter is replaced after 15…20 thousand kilometers of mileage. On diesel engines, respectively, in 10…15 thousand kilometers. However, according to numerous reviews of domestic car owners, especially those who live in large metropolitan areas and industrial areas, the mileage specified in the manual should be reduced up to two times. Therefore, if your car showed these typical signs of clogged filter, it makes sense to check its condition, and if necessary, replace it.

As for diesel engines, there is no throttle on them. Because of that, their air consumption is much higher. And if a diesel engine also has a turbine, it more actively sucks air from the atmosphere, which in itself speeds up filter clogging. The same reasoning is true for cars equipped with mechanical blowers (for example, some models from manufacturers Honda, Mini Cooper, Volkswagen, Audi, Mercedes Benz).
Many motorists combine replacement of an air filter and replacement of oil in the engine (that is, every 10 … 15 thousand kilometers of mileage).
Ways of replacement
There are two main ways to replace the air filter. The first is to delegate this procedure to the masters at the service station. However, due to its obviousness, we will not consider it. Let’s tell only that cost of such replacement is usually calculated on norm hours (each technical center can have its own method of calculation and various norms based on specificity of work and mark of the machine) and cost of the filter itself. And often service centers force car owners to buy filters only on the spot, and their price there can be higher than the market. On average, this is from 0.2 to 0.5 n/h, with a cost of 1800 rubles per 1 standard hour of operation, and in some cases the price of such a procedure is included in the cost of oil change.
The second way is to perform the procedure on your own. By money it is much more economical, because in this case you pay only directly for the filter itself. And where to buy an air filter is cheap – only you decide. The procedure is not complicated, but to perform it you need special tools.
Instructions for replacing the air filter with your own hands.
First of all, the required tools and materials must be assembled to start the engine air filter replacement procedure. Among them:

- a new air filter (when buying, make sure that it is exactly the same size as your car, it may not necessarily be original);
- a flat sting screwdriver (you may or may not need a flat stinger instead, depending on the type of filter box cover attachment);
- a clean rag;
- a compressor (preferably, but without it you can do without it);
- a dust brush (also optional).
On some cars, the body is additionally fixed in the seat by means of fasteners, bolts, plastic latches and metal clips… In this case, it is necessary to take care of the tool availability. On “Kangoo” car the cover of the filter box is fixed with bolts under “Torex” T27 or with a star.
Naturally, each car (and sometimes the same model, but with different engines) will have its own features in the attachment of the filter box and some nuances. However, in most cases (given that the procedure for replacing the filter is not complicated), the algorithm of actions will be as follows:
- Install the car on a flat surface, put it on the handbrake and shut down the engine.
- Open the bonnet.
- Unscrew the screws securing the air filter cover and then remove it.
- Carefully remove the old air filter so that dust and debris from it does not enter the air line or other parts of the hood.
- Close the inlet spigot with a rag.
- Use the compressor to blow dust out of the air filter housing. Use a brush instead of the compressor or combine both.
- Remove the rags from the air inlet connection.
- Install the new filter on its seat.
- Assemble the structure in reverse order.
In extreme cases, you can try to clean the old air filter as much as possible instead of buying a new one. However, this is only suitable if it is not possible to buy a new spare part.