Mercedes-Benz Fuel Pump Defect in Multiple Models

Mercedes-Benz USA (Mercedes) is addressing a significant fuel pump issue that has been identified in a range of its 2021-2024 vehicle models. This problem, which can result in a loss of drive power, potentially increases the risk of crashes and injuries. The affected models include various iterations of the GLE, GLS, C-Class, E-Class, S-Class, SL, GLC, CLS, AMG GT, and G-Class.

Origins of the Issue

Mercedes first became aware of this problem in early June 2022, following field reports from outside the United States. These reports described inconsistent power delivery in certain vehicles. Suspecting a fault in the fuel pump, Mercedes initiated an investigation and began retrieving fuel pumps from the affected vehicles for thorough analysis.

Investigation and Findings

Collaborating with their supplier, Mercedes conducted several tests, including examinations of fuel swelling behavior, structural damage, and notched impact resistance. The findings pointed to irregularities in specific raw material batches used for the suspect fuel pump impellers. These impellers, sourced from a sub-supplier, showed a deviation in the production process. As a result, they failed to meet the necessary material requirements, impacting the durability of the fuel delivery modules.

Potential Risks

The defect report clarified that certain fuel pump impellers might deform due to this material inconsistency, leading to contact with the fuel pump housing. This contact could create mechanical resistance and, in extreme cases, cause the fuel pump to shut down. Consequently, vehicles might lose propulsion, elevating the risk of accidents. Drivers might receive a warning message on the instrument cluster and notice the engine running roughly before the fuel pump stops working.

Extent of the Problem

Between May 14, 2022, and November 15, 2023, Mercedes received 1,901 warranty claims and field reports related to this issue. These are in addition to 2,031 claims and reports received between August 30, 2021, and May 5, 2023. Notably, there have been no reports of injuries, fatalities, or property damage linked to this defect.

Affected Vehicle Models

The fuel pump issue impacts a wide range of Mercedes-Benz models, including several AMG variants. The list includes: