Body and Underbody Maintenance — General Information (Audi A4 B5)

The overall condition of the body largely determines the value of the car. Maintenance itself is not difficult, but it requires regularity. Minor damage can lead to rapid corrosion and high costs for body repairs. It is very important to monitor hidden parts of the body, such as the bottom, inner surfaces of the wheel arches and the lower parts of the engine compartment.

The main part of routine maintenance is washing the body, preferably with plenty of water from a hose, which washes away all the dirt stuck to the body. It is important to wash away the dirt with water so as not to cause scratches when removing it in other ways. Wheel arches and subframes also require thorough washing, since dirt accumulates in them, retaining moisture and promoting corrosion. Paradoxically, it is a fact that in wet weather it is much easier to wash the bottom and arches of the car, since the dirt in hidden cavities has not dried. In wet weather, dirt on the bottom and in the wheel arches is washed away automatically while driving.

Periodically, except for cars with a wax-based anti-corrosion coating of the underbody, it is useful to wash the underbody and subframes with a jet of water under pressure or a steam jet, including the underhood space. At the same time, it is useful to carefully inspect the body for corrosion and damage to the protective coating that require repair and renewal. Such washes are useful for washing away oily dirt, which can be quite dense in some places. However, this type of washes also has disadvantages - when knocking dirt off the paintwork, it can be scratched, it can become dull from exposure to steam, a strong stream of water can break through the door seal and flood the interior and internal components of the doors (locks, loudspeakers and electric windows). Please note that these methods are not suitable for thin protective wax coatings, which can simply be washed off. Likewise, water and steam under pressure can penetrate into places where water usually does not reach and damage electrical components and fuel equipment. A jet of water can also break through the soft working edges of the seals, penetrating the lubrication system. Therefore, such washing should be carried out with extreme caution and, in any case, not regularly. It is much more reasonable to wash with a free stream from a hose. Although this will make the engine compartment look dirty. In this situation, use motor cleaning compounds that are applied with a brush and then washed off with water. After washing, take care to restore wax coatings, which can be destroyed by solvents. Normal washing is usually done with warm water and a suitable car shampoo. Bitumen stains are removed with white spirit, then with soapy water to remove traces of white spirit. When washing, make sure that no water gets into the air intake ducts, and keep their drainage tubes always clean.

After washing the paintwork, dry it with a soft chamois to avoid damage. Applying a layer of protective wax polish will provide additional protection from atmospheric influences. If the coating has become dull or oxidized, polish the body to restore shine with one of the many existing compounds. This requires little effort, but dullness of the paint occurs due to lack of regular washing of the body. Painting the body in metallic colors requires special attention, since it allows the use of only non-abrasive polishes to avoid damage to the varnish. Polished metals should be treated in the same way as paintwork. Glass is wiped with cleaning compounds to remove oil films from the glass. Never use polishes intended for the body or chrome coatings to polish glass.

This article was previously published on the resource AUDImanual.ru