Modern cars have technologically advanced engines that are highly susceptible to various kinds of contamination. Even the smallest particles of dirt can affect the engine’s operation and lead to faults or the complete destruction of the fuel system. Its protection is provided, among other things, by the fuel pump pre-filter, but for many reasons it can become clogged. What are the causes of this? How can we recognise it and what can we do about it? You will find answers to these questions in today’s post - read on.
What is the pre-filter responsible for?
Proper filtration of the fuel mixture is the basic condition for the correct operation of the engine. Delivering it at the right pressure, from the tank to the engine, is the job of the fuel pump. To perform its task it must be in perfect condition, and its main enemy is contamination getting into the fuel system.
Most modern fuel pumps are lubricated and cooled by the fuel flowing through them. In the event of any blockages and a clogged system, the proper operating conditions of this device may be disrupted. This can result in the pump running “dry”, which will lead to damage to the system and serious faults. Some electric fuel pumps are therefore equipped with a pre-filter intended to provide increased protection.
The mesh insert on the suction side is designed to capture and retain all larger contaminants that could pose a threat to the pump. To fully protect it, the filter must also separate water out of the fuel, because water can contribute to the corrosion of the fuel lines, the fuel pump and the injectors.
Pre-filter - causes of clogging
So what can contribute to clogging of the pre-filter and improper operation of the fuel pump? There is no single specific cause here, and many factors can have an influence, such as:
- contamination of the fuel tank caused by dirt getting in from the outside (during refuelling),
- corrosion arising in the fuel system as a result of water condensation,
- deposits forming inside the engine, e.g. as a result of a long standstill and ageing of the fuel,
- failure to replace fuel filters on time,
- damaged and cracked fuel lines,
- refuelling with low-quality fuel.
Fuel pump pre-filter - symptoms of damage
In the case of serious damage to the fuel pump, the car may even become immobilised - ignition will be impossible, because the necessary amount of fuel will not reach the engine. Before this happens, however, various symptoms may occur that will alert us that something is wrong, and they will progress gradually.
Clogging of the pre-filter and improper operation of the pump manifests itself in loud noise and overheating of the pump - this causes significant, noticeable drops in power. This will lead to various kinds of damage caused by overheating. It may cause the failure of one of the fuel system components and problems with starting and maintaining the proper engine speed.
A commonly encountered symptom of improper fuel pump operation is also the engine stalling right after starting or after pressing the accelerator. This significantly affects driving comfort - power drops occur, jerking during acceleration and loud, irregular noises.
Similar symptoms are, however, caused by many other problems with the vehicle, which is why if we want to be sure that the source of the problem is the pre-filter, we should go to an experienced mechanic. They will make a diagnosis and determine what steps need to be taken.
Cleaning the pre-filter
The mesh insert is not available as a spare part and therefore it should be cleaned from time to time. In doing so, the standard precautions for working with fuel systems must be observed. If we want to carry out the cleaning ourselves, the pre-filter must be pulled out of the suction connection with tweezers - this must be done very gently so as not to damage it. The filter must then be cleaned in fuel and afterwards carefully inserted back into the connection.
Regular engine cleaning as the key to the proper operation of the car
How can we take care of our car to eliminate the risk of faults occurring? The key is proper maintenance. Careful observation of the vehicle’s operation and quick reaction can save us from the need for costly repairs. Replacing the fuel pump, depending on the workshop and the car model, is an expense of around 1000-2000 zł. It is definitely better to take care of the fuel system regularly. How do you do that?
First and foremost, we must remember to regularly replace all the filters in the car. This way we can be sure that they will fulfil their role and effectively trap harmful contaminants. These can end up in our tank along with poor-quality fuel - we should therefore use trusted petrol stations, where all standards are observed.
Regularly cleaning the engine with an engine flush certainly will not hurt either. It will help get rid of unwanted dirt and restore the proper operation of all systems.
