The possible symptoms of a dirty air filter include: insufficient air intake, insufficient power, and unstable idle speed.

Let me talk about these two hazards in detail:
First, the air intake is insufficient and the power is insufficient. When the air filter becomes dirty, the air intake resistance will increase. When the engine does not get enough oxygen, the above symptoms will appear. If there is damage, it will accelerate engine wear and reduce engine life.
Second, if the air filter is dirty and the oxygen is insufficient, it will cause incomplete combustion, which will cause black smoke, a large amount of carbon deposits in the cylinder, black oil and loss of lubricating effect. In terms of engine wear, This greatly increases the wear rate, and at the same time there will be an increase in fuel consumption.

Air filter function:
1. The air filter is a device mainly responsible for removing particulate impurities in the air. When piston mechanical internal combustion engines and reciprocating compressors are working, if the inhaled air contains dust and other impurities, it will aggravate the wear of the parts, so an air filter must be installed;
2. The air filter consists of two parts: a filter element and a shell. The main requirements of the air filter are high filtration efficiency, low flow resistance, and continuous use for a long time without maintenance;
3. Generally, the air filter element should be changed once every two oil changes. The air conditioner filter element is recommended to be changed once every two years. In fact, these two filter elements are very cheap.

Air filter is also called air filter, its function is to purify the air entering the engine. For its maintenance, it is mostly cleaning and replacement. Generally speaking, when driving 7500-8000 kilometers, the air filter should be cleaned and maintained. Of course, the environment in each region is different. I would like to mention here that when there is a lot of sand and dust, the maintenance period should be shortened accordingly.