When cleaning a car ourselves or leaving it to professionals, we usually focus on the exterior and the interior. The engine bay often gets overlooked, since out of sight seems out of mind. However, even if you only lift the hood occasionally, it’s important to consider the practical side.
Helps identify potential malfunctions
Dirt and other debris can accumulate in the engine bay for various reasons. Dust, sand, or fallen leaves from trees appear naturally. The amount of debris may vary, though—if you drive on gravel roads more often, there will be significantly more.
However, some debris can result from car malfunctions. Leaky gaskets, seals, hoses, or pipes can allow various fluids to get onto engine components. In such cases, a clean engine bay makes it easier to spot leaks, as any dirt or residue appearing in the wrong place becomes immediately noticeable.
Just like washing the car’s exterior, cleaning the engine bay is difficult without a high-pressure water jet. Some drivers worry that this could damage the electrical components in the engine compartment. However, car cleaning experts say that properly maintained components are not negatively affected by it.
“While water and electronics don’t naturally mix, a car’s electrical system is protected against moisture, so when high-pressure water equipment is used correctly, it’s practically impossible to cause damage. However, if any negative side effects appear after washing the engine, theyindicate that there’s an underlying issue. Essentially, proper and thorough engine bay cleaning can help identify certain problems,” says Algirdas Plečkaitis, head of the car cleaning centers Hocus.
Experts warn that a heavy buildup of dirt can reduce the efficiency of the engine’s cooling system. For example, if the engine block is coated in a layer of grime, it acts as an insulator, making the engine more prone to overheating. The same issue can affect radiators and intercoolers.
Wash only at specialized car washes
While some drivers like to take care of their cars themselves, options for maintaining the engine bay at home are limited. Without knowing certain nuances or using cleaning equipment incorrectly, it’s possible to damage components under the hood.
Properly removing dirt also requires the right brushes and specialized—often strong—cleaning agents designed to remove various technical fluids or deposits. Of course, you also need to manage the water runoff after washing and dispose of it correctly. In short, the process isn’t simple, and mistakes can be costly.
Washing the engine bay is also prohibited at self-service car washes. Car cleaning experts emphasize that such bans exist because it’s practically impossible to control what personal cleaning products users bring, which could have a negative impact on the environment.
“The water filtration systems at self-service car washes are calibrated for the cleaning products actually used there. Extremely strong detergents, oils, or other technical fluids that may enter the drainage system when cleaning an engine bay cannot be properly handled by these systems,” explains A. Plečkaitis.
However, there are tasks drivers can—and should—perform themselves. Experts recommend checking the engine bay’s water drainage channels, as clogged drains can cause water to accumulate and, in large amounts, even leak into the car’s interior, potentially flooding components of the ventilation system.
How often should the engine bay be washed? It depends on how intensively the car is used and the environment. If you mostly drive short distances in the city, washing the engine bay once every year or two may be sufficient. However, for frequent rural driving, especially on unpaved roads, it’s recommended to clean the engine bay two to three times a year.
