Doncaster34 Posted May 28 Share Posted May 28 Greetings, everyone. After doing maintenance on my Vito V6 with the OM642 engine (equipped with a diesel particulate filter), I am now experiencing an abundance of smoke.Prior to the issue, my work routine was ordinary with no smoke. This allows me to rule out injector failure and a malfunctioning EGR cooler, since the coolant level remains consistent and clean. Completed tasks: - seals for the oil cooler - The swirl flaps were removed since they were trapped in the open position with a resistor modification prior to the work. All seals were replaced during the maintenance, and both the fuel and air filters were also replaced. - The seals on the injectors have been replaced. - A new return pipe has been installed since the previous one was leaking significantly on two injectors, causing a diesel leak. Additionally, the injector chamber was found to be filled with diesel. During a lengthy journey, I observed a warning on the dashboard indicating that the oil level was too high. In response, I replaced the PCV valve and breather. Following this maintenance, I decided to change the oil. To do so, I added a flush and ran the engine for approximately 10 minutes. At this point, there was no smoke present. However, it is possible that I made an error during the subsequent step, which involved changing the oil and filter. I opted for Fuchs Titan GT1 5w40, a brand I have not previously used, but is compatible with Mercedes-Benz vehicles.- I inadvertently initiated a DPF regeneration process while using Xentry, resulting in the release of smoke. I now see that this action is likely responsible for 99% of the issue. Consequently, the regeneration process now attempts to complete every time I start the vehicle. Is there a method to halt the process of regeneration before it is fully completed?Is there any way to resolve the issue of not being able to smoke for 20 minutes in my location, such as doing an ECU reset or trying other methods? Could there be another issue here? I appreciate any assistance you may provide in advance. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 Update: I have successfully performed a forced diesel particulate filter (DPF) renewal using xentry. Initially, there was a significant amount of smoke for the first 2 minutes, but it cleared up thereafter until the regeneration process was completed, which took around 20 minutes. The temperature throughout the regeneration process reached roughly 630 degrees. The smoke dissipated. I took the van for a test drive and drove it for approximately 15 minutes. During the drive, the coolant temperature increased to around 70 degrees Celsius and there was no smoke. However, when I accelerated and shifted from 3rd to 4th gear, I heard a sound resembling a turbo or boost whining, and then the vehicle went into limp mode. I drove back to the starting point and checked for error codes, which revealed the presence of code 2089-008 b18. This code indicates a malfunction in the exhaust back pressure sensor, which is a plausible explanation for the issue. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 Replaced the exhaust back pressure sensor with a new, authentic one. The error code is no longer appearing, even during intense acceleration. However, sometimes I can still hear a high-pitched sound from the turbo between 3000 and 4000rpm.(perhaps a leakage of compressed air someplace). How can I perform a diagnostic test on the Mass Air Flow (MAF) sensor for this specific engine? Will the engine stop if I disconnect it while it is running? When I detach my device, the engine noise changes somewhat but does not cease. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 Currently, I am experiencing stress as the code has returned, but the vehicle is no longer entering limp mode. The specific code is 2641-008. I have previously replaced the rear exhaust sensor and also the MAF sensor as a precautionary measure. I kindly want assistance or suggestions, as I am on the verge of surrendering. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 There has been no advancement in my current situation. I am contemplating the reason behind the rapid decrease in exhaust back pressure at about 2000 rpm. It might be due to the activation of the turbocharger or the engagement of the exhaust gas recirculation (EGR) system. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 I suspected that the catalytic converter was clogged, so I removed the catalytic converter from the diesel particulate filter (DPF). However, the pressure did not change. Then, I removed the bolts between the turbocharger and the catalytic converter, and the pressure in the exhaust system decreased as expected. Quote Link to comment Share on other sites More sharing options...
BENZE220AMG Posted May 28 Share Posted May 28 Regrettably, I am unable to assist you, pal. I empathise with you. It seems like you are not receiving much assistance from this group of people. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 Thank you for comprehending. Now, it is essential to complete the task since I have invested a significant amount of time and money. Until now, I have considered the possibility of a catalytic issue, but I remain unconvinced that this is the problem. The exhaust flow appears to be functioning well at idle, as I can feel it up to a distance of 1.5 metres. Additionally, I have attempted another forced regeneration using cataclean in the fuel and DPF/Catalytic cleaner foam inserted into the catalytic converter through the temperature sensor slot.The oil was replaced thereafter. Upon reevaluation, I found that the back pressure remained unchanged at approximately 1500mpa before and after regeneration. However, upon further investigation, I observed that the EGR valve was randomly opening and closing, causing the back pressure to fluctuate between 1400mpa and 1600mpa. As a result, I have discarded the hypothesis that the catalytic converter is obstructed. So, the question is: what might be the reason of elevated back pressure when another sensor is added to the system? It is possible that the back pressure sensor is faulty, despite being new. It seems to be very sensitive, since it is displaying a reading of 1500mpa instead of the expected 1000mpa. I have purchased an additional sensor, namely a more affordable Chinese one, in order to verify this. Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 Today, when attempting to detach the sensors individually in real-time, I saw that removing the MAP and MAF sensors resulted in a decrease in back pressure. Consequently, I have placed an order for a new MAP sensor after seeing that the values it provides are over the acceptable pressure range. Quote Link to comment Share on other sites More sharing options...
BENZE220AMG Posted May 28 Share Posted May 28 In my opinion, I would recommend obtaining an accurate diagnostic from a reputable independent garage or expert prior to investing a significant amount of money on individual components. Best wishes Quote Link to comment Share on other sites More sharing options...
Doncaster34 Posted May 28 Author Share Posted May 28 It would be too simple to surrender. Arranged, task completed. Conclusion: The back pressure sensor that was initially purchased, which was an expensive "Original" sensor made in Germany, was found to be incorrect. It displayed a pressure reading that was approximately 400hpa higher than it should have been. It is possible that this sensor is either an absolute or relative sensor, as indicated in this document: https://static.nhtsa.gov/odi/tsbs/2017/MC-10158249-9999.pdf. However, it is worth noting that this sensor has the same part number A0051535028. I recently purchased the most inexpensive item I could find on eBay for 11 pounds. It successfully functioned and featured a Mercedes logo, indicating it was manufactured in China. As a result, I now have appropriate back pressure, although the boost pressure sensor is slightly beyond the desired range. However, I have already ordered another inexpensive replacement from eBay, which will arrive in a day's time, also priced at 11 pounds. I am pleased that everything is now resolved and the engine sounds pleasant and operates smoothly. This information may be beneficial to someone. Quote Link to comment Share on other sites More sharing options...
BENZE220AMG Posted May 28 Share Posted May 28 Congratulations for a job well executed! I'm pleased to hear that you were able to resolve the issue successfully. Well done!👍🏻 Quote Link to comment Share on other sites More sharing options...
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