Renault Master LML35 B-NESS ENERGY DCI Overview
The Renault Master LML35 B-NESS ENERGY DCI arrived with persistent DPF related faults that were impacting engine performance and triggering warning lights. Diagnostic checks confirmed fault code DTC P253F29, indicating engine oil dilution caused by incomplete DPF regeneration. This issue had led to excess fuel contaminating the oil and restricting the Renault Master Exhaust System, reducing efficiency and increasing back pressure.

To resolve this, a professional DPF solution was applied to restore proper regeneration and improve exhaust flow. As the engine oil had become contaminated, a full oil change was carried out to remove the diluted oil and reinstate proper lubrication. This combined approach restored performance, improved responsiveness, and protected internal engine components from further wear.

Size and Practicality
Due to the vehicle’s high top and long wheelbase configuration, careful planning was required to safely inspect and carry out the work. Attention was focused on ensuring the Renault Master Exhaust and emissions system could operate efficiently within a commercial setting, restoring reliability for day to day use.

Safety and Features
With the DPF system supported and fresh oil installed, the vehicle now benefits from improved engine protection, smoother running, and reduced risk of recurring faults. Resolving the oil dilution issue ensures long term durability, which is essential for a working van.

Exhaust System and Emissions Work
The Renault Master Exhaust System was a key focus, as DPF restrictions were causing increased back pressure and poor combustion. By improving exhaust flow and supporting correct regeneration, we resolved the underlying issue, reduced strain on the engine, and restored overall efficiency and emissions performance.