The diesel particulate filter (DPF) regeneration is designed to clean the accumulated particulate matter or soot from a diesel engine’s exhaust system. This is an important procedure, especially on the OM642 diesel engine’s emission control system, as it helps to reduce emissions of harmful particulates into the atmosphere. In a Mercedes vehicle, the DPF regeneration process occurs automatically, but sometimes, it may need to be initiated manually.
The cost of DPF regeneration varies and can be influenced by factors such as the make and model of the vehicle and the location. It is essential to understand the DPF regeneration process, its importance, and the symptoms of a DPF that needs cleaning to keep your Mercedes diesel engine running smoothly and efficiently. DPF regen can also be initiated with a YOUCANIC scanner.
Mercedes-Benz Diesel Particular Filter (DPF) may build up excessive soot content, leading to exhaust restriction, and eventually, the check engine light turns on. If you have a diesel Mercedes-Benz and are quoted a new DPF filter, carry out a forced DPF regeneration. In some cases, DPF regeneration may need to be done twice to clean a clogged DPF. Replacing the DPF is rarely required and may only be required in sporadic cases. DPF replacement is typically unnecessary if the vehicle has less than 200,000.
Over time, the DPF can become clogged with particulate matter, leading to several problems. Some common DPF problems include:
- Regeneration issues: If the DPF does not regenerate (i.e., burn off the accumulated particulate matter) correctly, it can become clogged and restrict exhaust flow, leading to reduced engine performance.
- Engine warning lights: If the DPF becomes clogged, it can trigger a warning light on the dashboard. This typically indicates that the DPF needs to be replaced or cleaned.
- Increased fuel consumption: If the DPF becomes clogged, the engine may have to work harder to push the exhaust gases through the restricted filter, increasing fuel consumption.
- Reduced engine power: If the DPF becomes severely clogged, it can restrict exhaust flow to the point where the engine’s performance is significantly reduced.
To avoid DPF problems, it is important to follow the manufacturer’s recommended maintenance schedule, which typically includes regular DPF regenerations. Driving style and conditions can also impact the DPF, so it is important to drive in a way that promotes DPF regeneration, such as avoiding short trips and excessive idling.
Mercedes-Benz DPF Regen Tools
- YOUCANIC Full System Scanner
- Mercedes-Benz Star Diagnostic Scanner C3, C4, C5
- Autel MaxiDAS Full System Scanner
How to Regenerate Mercedes-Benz DPF
This guide will show you how to perform DPF regeneration with a diagnostic scanner. This is called a forced regeneration and can be performed if passive DPF regeneration has failed.
- The vehicle will need to be driven.
- Two people are required.
- DPF regeneration takes about thirty minutes.
- No other fault codes should be active except DPF – Ensure no engine-related fault codes are present (they will prevent the DPF from starting)
- Ensure there is at least 20% fuel in the tank.
- Risk of fire. The exhaust temperature is exceptionally high during this procedure and can reach 700 °C.
Here is how to regenerate Mercedes DPF: To perform this procedure, you will need a Mercedes-Benz Diagnostic Scanner that supports the DPF regeneration function. The menu names may vary slightly between scanners but are the same for all scanners. DPF regen steps below apply to Mercedes Star Diagnostic C3 and C4 scanners.
- Connect your scanner to the diagnostic port under the dashboard. Start the engine and let it idle in Park.
- Power up the scanner and select the Mercedes-Benz model. Select Control Units.
- Next select Special Functions
- Select Regeneration of Diesel Particulate Filter when driving.
- Once the DPF regeneration is completed successfully, don’t turn off the engine immediately. Instead, keep the engine running until the temperate sensor upstream of the diesel particulate filter (B19/9) has dropped below 400 degrees Celcius.
- After DPF regeneration, clear the ECU and make sure no other fault codes are present.
- Test the vehicle for fifteen minutes to ensure the check engine does not come back on. If the check engine light still comes back on
- Follow the instructions under the DPF regeneration menu.
- You will need to drive the vehicle at 35mph or higher speeds.
- Try to keep engine RPMs between 2000 and 4000. If you slow down, downshift the transmission gear so that the RPMs remain in the recommended range.
- Two people are required to complete this test.
If oil leaks near the exhaust system, Mercedes DPF regeneration should not be performed. It is important to realize that passive DPF regeneration is usually activated periodically, but certain conditions must be met. Usually, the regeneration process occurs on extended highway trips without the driver realizing it. If passive DPF regeneration fails frequently and forced DPF regeneration is often required, it could indicate an underlying problem with the engine.
DPF Regen Cost
The cost of DPF regeneration can vary depending on whether you have it done by a dealership or perform it yourself using a professional scanner.
- Dealer regeneration: DPF regeneration costs between $250-$800 at a dealership, as dealerships typically charge a premium for their services. The exact cost will depend on the dealership and the type of vehicle you have, but it can range from several hundred to several thousand dollars. In addition, the dealer will require you to replace certain parts before you can run a regen on the DPF filter.
- DIY regeneration with the professional scanner: If you choose to perform DPF regeneration using a professional scanner, the cost will be lower than at a dealership. The cost will depend on the scanner and any other tools you need to purchase, but it can still be several hundred dollars.
Remember that performing DPF regeneration requires a certain level of mechanical expertise and a thorough understanding of the process. If you’re uncomfortable working on your vehicle, it’s best to have the regeneration done by a professional. In addition, to perform DPF regen on a Sprinter or BlueTec vehicle, you must ensure no active fault codes in the Engine Control Unit.
Regardless of the method you choose, regular DPF regeneration is important to maintain the performance and longevity of the DPF, so it’s worth investing in the cost to ensure your vehicle is running smoothly.
Passive DPF Regeneration
Passive DPF regeneration is when the vehicle starts the DPF regeneration automatically while driving to burn off soot build-up on the DPF. Passive DPF regeneration only starts when certain conditions are met. Typically, after driving on the highway for at least ten minutes and when no fault codes exist in the ECU, if the required conditions are not met, passive DPF regeneration will fail, leading to excessive exhaust soot built up on the DPF.
Forced DPF Regeneration
If multiple attempts to start passive DPF regeneration fail, your mechanic may have to force DPF regeneration. One of the most common indications you need to regenerate the DPF filter is the engine light comes on, the vehicle may get stuck in limp mode, and a fault code indicating soot content is too high gets stored in the ECU.
Symptoms of a clogged Mercedes Diesel Particulate Filter (DPF) with high exhaust soot content include:
- Check engine light stays on
- Loss of power
- Limp mode
- A decrease in fuel economy
- No throttle response
- Car struggles to start.
- Failed emission test
A variation of the following fault code may also be stored in the ECU:
- P243609 – The soot content of the diesel particulate filter is not ok or too high. There is a component fault.
What are the symptoms of a clogged DPF filter?
The first thing you will notice if there is a problem with the DPF filter is that the check engine light comes on. DPF regeneration failed to start automatically at this point, usually because of too many short trips. A mechanic can follow the instructions below to carry DPF regeneration. In some cases, if DPF regeneration is not started for an extended period, the vehicle may go into limp mode.
Do I need to carry DPF regeneration myself?
Yes, but you need a professional scanner that can start DPF regeneration.
Can I remove the DPF system?
Several aftermarket kits allow you to manipulate the Engine Control Unit and remove the Diesel Particulate Filter and, in some cases, the BlueTec system. You may even find a company that will remove the DPF. Removing the diesel particulate filter is not legal in most countries. Vehicles with no DPF have much higher harmful emissions.
While removing a Mercedes-Benz DPF filter is illegal in most countries, cleaning the DPF system is legal and a more cost-effective alternative to replacing the DPF. Many companies offer DPF cleaning services, and a quick search should reveal a few places near you. DPF cleaning is typical for trucks, but the same procedure can be performed on diesel Mercedes-Benz vehicles.
We hope you find the Mercedes Diesel Filter (DPF) Regeneration Procedure guide helpful. Check these troubleshooting and repair guides for more help on your Mercedes-Benz.
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