Manifold for O.M.651 inlet

[DreamyDusk]

Greetings, individuals.

Has anybody inside this forum successfully performed the replacement of the intake manifold on a Mercedes-Benz Vito 114 CDI W447 OM651 model from the year 2018? The observed symptoms include the activation of limp mode, absence of boost, and the presence of error codes P0299 and P2261. I have made modifications to the boost sensors, transducers, crossover valves, and EGR system. There are no apparent hoover leaks. The turbo seems to be in satisfactory condition, with no observable damage to the intercooler or hose pipes. Additionally, the turbo actuator exhibits unrestricted movement when a vacuum pump is used.

Subsequently, the intake manifold was addressed, since it has been identified as a prevalent concern pertaining to the OM651 engine.
The fuel filter housing and related components have been removed, allowing for visibility of a significant portion of the upper section of the manifold. However, despite this examination, no apparent vacuum leaks or smoke emissions have been seen.
When using a smoke machine, the inquiry arises as to whether the manifold may still be the underlying issue. Consequently, one must consider the possibility of replacing the manifold, despite the laborious nature of the work and the undesirability of having to disassemble and reassemble the components. I express my gratitude in advance.

[MercedesFan2022]

The occurrence of a fractured bolt is most often seen in the lower region, typically positioned as the second bolt from the anterior end. Typically, a smoke test is used to identify the issue. However, by directing one's attention towards the oil filter housing and using a light, it is possible to see the presence of aluminium fins associated with the oil cooler. If there is an oily residue present on the cooler, it might be inferred that there is a leakage in the manifold.

[MercedesFan2022]

A significant number of individuals have frequented my establishment since that time.

[MBcarOWNER]

I have the same problem...
Upon conducting an inspection while the smoke machine was in operation, I saw the area around the oil cooler under the manifold. There was no presence of black soot, indicating a clean condition with no apparent signs of leakage.
What methods may be used to assess the functionality of the flap motor?

[MercedesFan2022]

I am of the opinion that the aforementioned situation does not constitute a leak.

[MBcarOWNER]

Is it possible that the issue is caused by a malfunctioning flap motor?
What other factors might potentially lead to the occurrence of codes? The codes P0299 and P2261 refer to specific diagnostic trouble codes (DTC

[MercedesFan2022]

Although I am not very knowledgeable in the field of commercials, it seems that there are two relevant codes pertaining to the issue at hand: underboost and changeover valve. I have seen an OM651 engine installed in a w166 ML vehicle with the presence of a changeover valve code. The issue at hand was to a solenoid valve responsible for the operation of the changeover valve. The solenoid on the ML was positioned on the right side of the engine, towards the rear, under the EGR cooler flap actuator. The vehicle had an elongated pipe that extended along the rear of the engine and traversed over the upper portion of the bellhousing. In this scenario, it may be concluded that the solenoid valve was faulty. It may be worthwhile to consider examining that. If the component in question is malfunctioning, it will also generate a diagnostic trouble code indicating an underboost condition.

[MercedesFan2022]

Please peruse the following text. It is believed that the engine in question is equipped with a dual turbo configuration. The transition valve facilitates the conversion between the smaller and larger turbochargers. The system operates under hoover control, with a solenoid being responsible for the switching of the hoover.

[MercedesFan2022]

https://diysprinter.co.uk/reference/Int ... OM_651.pdf

[MercedesFan2022]

Please go to page 26 for items 124, 125, and 126. In the w166, the solenoid is located on the other side of the engine. It is presumed that there will be a resemblance.