What problems to expect if engine oil gets into the air filter, and what to do
Every experienced car owner at least once in his biography has seen an oil-stained air filter. Of course, this is a symptom of a malfunction, but how serious? Portal "AvtoVzglyad" figured out such a dirty issue.
The situation when, during a scheduled maintenance, the master takes out the air filter and shows the owner distinct traces of engine oil is like a horror movie. Getting fuel and lubricants into the "air intake" is a so-so symptom. After all, this is a thick hint at the malfunction of the most expensive and difficult to repair unit of any car - the engine. Given the widespread desire to carry out a comprehensive replacement of the unit, instead of disassembling and looking for the cause, the score will be six figures. But is the devil as terrible as he is painted?
The first and key reason for oil getting into the “air” is clogged channels in the cylinder head. Here, many hours of traffic jams, and non-observance of the service interval, and oil "at a discount" immediately come to mind. Undoubtedly, such an approach will quickly send a complex modern engine to a landfill, and it is many times more profitable for a dealer to convince his client that the unit is unsuitable for repair. But it’s not worth agreeing to another loan right away, because at least you can try to decoke the engine - there are a lot of methods and car chemicals. Moreover: the oil channels of the “shirt” are far from the only reason for engine oil to enter the air filter housing.
This "trouble" can also occur due to increased wear of the rings on the pistons, which are responsible for the compression inside the cylinders and the thickness of the oil film on the walls. If the exhaust turned gray, like an evening society at a regional “glass”, then it would not be bad to measure the compression in the cylinders before putting it in for repairs - it is likely that the trouble lies precisely in the rings. They wear out, the pressure in the crankcase increases, and the crankcase ventilation valve begins to dump excess. Where do you think? That's right, in the air intake system. That is directly to the air filter.
By the way, about the PCV valve, aka crankcase ventilation. It, oddly enough, is also periodically cleaned and even changed. The abundance of low-quality, often counterfeit motor oil, which has now overwhelmed the domestic market, despite all the attempts of oil companies, as well as difficult operating conditions - the city with its traffic jams is no easier to tolerate by any engine than the hardest off-road - do their "dirty deed".
And the “first sign”, signaling the need to carry out a “big cleaning” in the engine, will be just the clogging of that very forced crankcase ventilation valve. Its appearance will tell you the order of further actions, but practice shows that two or three years in the "stone jungle" for this node is the absolute limit.
It is a pity that this operation is not in the operating manuals, as well as in the dealer “rolls”, because checking the operation, as well as cleaning or replacing the PCV sensor, significantly increases the life of the engine. Especially complex modern, burdened by a turbine. After all, it is a faulty sensor that can cause the very increased pressure inside the crankcase and the subsequent ejection of oil directly into the air filter.
The oil in the air filter is an undoubted symptom of incorrect engine operation, but it is impossible to draw a conclusion and make a decision about the future fate of the car solely on what you see. It is important to realize that the engine requires attention, and the machine as a whole requires an investment. Moreover, the amount of invested funds often depends on the honesty of the master and the knowledge of the owner.
