Diesel filter: what is it, how does it work and when to change it?

The diesel and gasoline filter can be the forgotten part of your car's periodic maintenance. It is an essential component for the correct operation of the vehicle and will ensure that there is no breakdown in the fuel system or in the engine. What is the diesel fuel filter? How does it work? How often should it be replaced? We solve all your doubts.

This filter is present in all new or used Mercedes equipped with an internal combustion engine, regardless of whether it is diesel or gasoline. Each engine has its specific fuel filter, which is recommended to be replaced periodically to avoid a possible mechanical failure.

What is the diesel filter and what is it used for?

The diesel and gasoline filter is a component that is integrated in the fuel injection system of your car. It has a cylindrical shape and inside it there is a filter made of porous material that cleans the fuel of impurities before it enters the combustion chamber through the injectors.

By using a fuel filter in good condition, the diesel and gasoline are cleaned of any residue. In this way, the dirt that the fuel may contain and that settles at the bottom of the tank does not reach the injection circuit, the pressure pump, the injectors and the feed circuit.

In addition, in the case of diesel cars, the diesel filter has a double function. In addition to the aforementioned tasks, it removes moisture, preventing the appearance of corrosion in any metal component of the fuel system and the engine. Its operation is basic, but it is vital to avoid a breakdown due to obstruction in the vehicle's fuel supply system.

When to change the diesel filter?

Replacing the fuel filter is part of the Mercedes A and B Maintenance work. The filter must be replaced periodically, a task that will indicate the Mercedes Assyst Plus system through the vehicle's instrument panel. Once the warning has been triggered, you must go to one of our Official Mercedes Benz Workshops of Grupo Concesur for the replacement.

The useful life of a diesel or gasoline filter is about 60,000 kilometers. However, it is not advisable to delay the change too long. So, how often should the diesel filter be changed? It is best to replace the fuel filter every two service intervals or two years, whichever comes first, to prevent excess dirt from clogging it, causing a loss of effectiveness.

Dirty diesel oil filter: main causes

What can cause the diesel filter to be dirty? Mainly, its deterioration is caused by the residues that accumulate in the fuel tank. For this reason, it is advisable not to rush the tank, avoiding as far as possible that it does not reach the reserve. You should also avoid refueling at a service station where the tanks are being filled or have just been filled. Impurities will not yet have settled to the bottom, so you will be filling up with dirtier fuel than usual, forcing a possible clogging of the diesel or gasoline filter.

What happens if the diesel filter is dirty?

One of the consequences of a dirty diesel filter is low or erratic pressure, with the corresponding loss of power, jerking or high fuel consumption. At low engine speeds, if the filter is too clogged, it may even stop the engine. It is therefore important not to overfill the tank of the car and to replace the filter periodically.

And what do you notice when you change the diesel filter? If the filter was too dirty, you will notice that the car responds smoothly, revs up naturally and maintains a stable idle speed. You may also notice that the fuel consumption goes back down to the usual averages.

Diesel oil filter price

The fuel filter is a considerably inexpensive replacement. The price of the diesel filter can range between 30 € and 40 € in the case of the most complex ones. In addition, a diesel filter replacement in a workshop is a repair that does not take too much time and can cost less than €100.

In Grupo Concesur we have an experienced after-sales service in which we take care that your Mercedes always looks like the first day. We are an Official Mercedes Benz Service with more than 47 years of experience in the sector. We only use original Mercedes spare parts and we have technicians specialized in detecting and repairing breakdowns. If you haven't done it yet, make an appointment at your nearest workshop and tune up your car with the best guarantees.