NHTSA Complaint #11700103 — 2016 BMW X3

The low-pressure fuel temperature/pressure sensor failed internally, causing diesel fuel to intrude via capillary action into the engine wiring harness and ultimately contaminate the Digital Diesel Electronics (DDE) control unit (ECU). The failed components (sensor, harness, DDE) are available for inspection upon request at BMW of Loveland, CO. My safety was put at risk in two primary ways: Engine Stalling Risk: The DDE is the engine control unit. As the fuel contaminated the electrical connections, the engine's reliability was compromised, creating a significant risk of sudden engine stalling while driving in traffic or at high speeds. Fire Hazard: The intrusion of diesel fuel—a combustible fluid—directly into the electrical wiring harness and the DDE created a clear fire hazard. Fuel near active electrical components poses a serious safety risk. Inaccurate Temperature Readings: The EGT (Exhaust Gas Temperature) sensor received incorrect readings due to the DDE/wiring issue, leading to potential engine damage due to excessively high exhaust temperatures. The problem has been confirmed by BMW of Loveland. The Service Director and their technical team identified the root cause in less than one day and confirmed it requires the replacement of the sensor, harness, and DDE. This was also validated by an internal BMW technical support case (TSARA). Gebhardt BMW failed to diagnose the issue correctly over three prior attempts starting in June 2023 through Aug 2025. Prior symptoms appeared over a period of months and included: Intermittent check engine light/MIL. Multiple, confusing diagnostic fault codes (related to air mass, charging pressure, and DPF efficiency). Increased frequency of DPF regeneration intervals.