The soot filter on BMW diesel cars is installed on vehicles with diesel engines to maintain the quality of exhaust gases in accordance with strict standards. In a properly functioning engine, the DPF ensures the cessation of soot and carbon particle emissions, which are dangerous to human health. However, its service life is predetermined and does not cover the entire lifespan of the vehicle.
For most BMW models equipped with DPF filters, the service life is approximately 200,000 kilometers. In gasoline cars, a catalyst is used, about which we have written in a separate article.
Diesel Engine Cars
When buying a new car, there should be no problems for several years. Even if the car is used for intercity trips, there should be no issues related to its operation. The only exception is the phenomenon of the oil level in the engine, which should be closely monitored.
As a result of automatic DPF regeneration, the fuel injection phase is extended, and the dose gradually increases. If the process takes 20-30 minutes, everything is fine, and the filter will not clog too quickly.
If driving primarily in the city on segments of 10 to 15 kilometers, spending time in many traffic jams, the subsequent processes after combustion are not completed. As a result, not only does the BMW soot filter clog more quickly, but there is also significant dilution of the engine oil with excess unburned fuel, which runs down the cylinder walls into the oil pan. Hence the reports of exceeding the maximum oil level in the engine from automatic measuring systems.
To avoid leaks from the engine, the oil should be drained. For environmental protection and necessary precision reasons, this operation can only be performed in an auto service.
Additionally, more frequent checks should be carried out — every 15–20 thousand kilometers, not every 30,000 kilometers (the recommended interval). This will help avoid surprises related to sudden damage to an unlubricated engine or a smoothed turbocharger.
Soot Filter on BMW Diesel, Problems and Solutions
In the vast majority of imported vehicles, there is a problem due to the operation of the BMW soot filter. Of course, a service center can check the degree of filter clogging and its working history (tripping) using diagnostic computers.
Read other useful BMW care tips.
What to do if BMW already reports a problem with the DPF filter or it is in emergency mode (displaying the engine indicator, DPF filter indicator, no power)?
Cleaning the BMW Soot Filter
If its clogging degree and exhaust gas pressure do not exceed the allowable pressure values by several times, you can attempt chemical cleaning and regeneration during driving using a diagnostic computer.
A properly performed procedure ensures further filter operation for a period similar to a new filter, that is, a mileage of 150 to 200,000 kilometers.
Replacing the BMW Soot Filter with a New One
New filters are offered from BMW catalogs, and there are also numerous analogs available. The prices of original filters deter potential customers, varying depending on the engine version and its age.
Prices for analogs are highly competitive because they are already available at 2-3 times cheaper than the originals. They provide a corresponding technical level of performance and correct engine and accessory operation.
DPF Filter Removal
Unfortunately, besides the low price, the operation does not provide any advantages and can cause many technical and formal problems. A BMW without a filter cannot be fully operated.
Depending on the engine version and age, it may react differently to sudden changes in combustion parameters transmitted by pressure sensors and engine control unit sensors. At best, the engine light will illuminate, and at worst, the engine may go into emergency mode (power and vehicle speed limitation).
The software changes offered with BMW soot filter removal do not solve the problem but only disable some warnings displayed to the driver. However, the most important issues are the formal problems we may encounter during the operation of such a vehicle.
Extended technical tests announced over a long period will also include the quality and exhaust emissions of gases.
