Air filter and sound-absorbing pipe (Fiesta 4)

The air sucked in by the engine contains dust and dirt particles that should not get into the combustion chambers, as they act as an abrasive on the cylinder walls and cause premature wear of the pistons and cylinder working surfaces. The air filter element cleans the air entering the engine cylinders and is located in the air filter housing (sound-absorbing pipe). The sound-absorbing pipe performs a very important task: it calms the uncontrolled rotating flow of fresh air and at the same time suppresses the noise that occurs when air is sucked in. In the Fiesta, the sound-absorbing pipe consists of a plastic housing and a fine-pored, accordion-shaped air filter element.

Air filter maintenance

The intake air passes through the air filter housing, inside which the filter element is fixed with two plastic gaskets. The entire air flow passes through the filter, while dust and all dirt particles that accelerate engine wear are retained by the filter element. Larger foreign particles, such as insects or grains of sand, remain in the air filter housing. The air filter and filter element function normally only if they are constantly checked and maintained in good condition. A dirty filter element does not clean the intake air, which leads to a deterioration in the fuel-air mixture, an increase in the toxicity of exhaust gases, a decrease in engine power with an increase in fuel consumption.

Cleaning the air filter element

The filter element and oil catcher in those engine versions where it is installed must be cleaned at least once a year and changed once every two years. Filter elements must be purchased in specialized stores, and they do not necessarily have to be original, but in any case, pay attention to the quality.



SEQUENCE OF WORKS



Fig. 7.1. Location of air hose clamps on the intake manifold and air flow meter

1. Loosen the air hose clamps on the intake manifold and air flow meter (Fig. 7.1). In a diesel engine, loosen the clamps on the intake manifold and air filter housing.

2. Unscrew the air filter cover, lift it and remove the filter element.



Fig. 7.2. Location of the oil trap (1) in the air filter housing



3. Before installing a new element, clean the filter housing and cover with a lint-free cloth or blow with compressed air. If oil separator 1 (Fig. 7.2) is installed, clean it thoroughly with gasoline. Make sure that the seals of the new filter element fit tightly to the surfaces of the filter housing.

Cleaning the filter element

SEQUENCE OF WORKS

1. Tap the filter element on a hard surface to loosen coarse dirt particles.



Fig. 7.3. Using compressed air to clean dust from a paper filter element

2. If it is necessary to remove fine dust, the filter element must be blown out with compressed air (Fig. 7.3):

– direct the air stream only from the bottom up of the filter element. Otherwise, you will press dust into the filter pores;



– Never clean the paper filter element with liquids. In this case, the filter pores will be completely clogged, which will lead to a decrease in engine power and an increase in the amount of harmful substances in the exhaust gases.

3. When installing the filter element, always ensure that the sealing plastic rings fit tightly against the bottom of the housing and seal the cover.