Here’s an important aspect of servicing diesel engines that you should be aware of.
Just take a look at this photo and admire its condition:
 
 
This is a typical state of the intake system in urban diesel engines after approximately 60,000 kilometers.
WHERE DOES ALL THIS DIRT COME FROM?
These are the consequences of the Exhaust Gas Recirculation (EGR) system. It’s a whole separate story, but in short, instead of harmful emissions going straight out into the environment, they make another round inside the engine.
IS IT HARMFUL TO THE ENGINE?
No, not necessarily. However, when the intake manifold starts to get heavily clogged, it can lead to expensive repairs (such as failure of swirl flaps, for example).
WHAT CAN BE DONE ABOUT IT?
Regular cleaning is the solution.
HOW DOES THE CLEANING PROCEDURE WORK?
It’s better to seek assistance from a specialized service center and request an intake system cleaning that involves disassembly. Non-disassembly methods are less effective and won’t help much if the situation is like the one shown in the photo.
IS THERE ANYTHING THAT CAN PREVENT THE INTAKE SYSTEM FROM GETTING CLOGGED WITH DIRT?

Yes, there are two options:
– Buy a gasoline-powered vehicle.
– Disable the EGR system.
However, we recommend simply performing periodic cleaning of the intake system. As long as the EGR system is operational, let it do its job.

Thank you for your attention.