What causes frequent fuel nozzle tripping in BMW X6?
2 Answers
Frequent fuel nozzle tripping in BMW X6 may be caused by design issues or product quality problems with the fuel nozzle. Design issues: If it's a design problem, it could be due to poor fuel tank venting performance during refueling. This may result from inadequate fuel tank refueling tests, where the venting performance is related to the fuel tank's liquid level control valve or level tube. Product quality problems: If excessive gasoline vapor is generated during refueling, it can clog the vehicle's charcoal canister, preventing complete vapor discharge. This leads to blockage of the vent hole by large amounts of gasoline vapor, creating high pressure. The system then mistakenly interprets this as a full tank and stops refueling, causing the nozzle to trip.
My BMW X6 also frequently encountered the annoying issue of the fuel pump nozzle tripping. At first, I thought it was a problem with the nozzle itself, but later I realized that the nozzle would trip frequently whenever the fuel tank was close to half full. The mechanic removed the underbody shield to inspect the charcoal canister system and found that the vent hole of the charcoal canister was clogged with dust and oil residue, causing poor venting in the fuel tank. When refueling, the gas pressure inside the tank would push against the nozzle's sensing device, mistakenly triggering the trip. Additionally, the fuel evaporation system pressure was tested, and the high pressure reading indicated a blockage in the air passage. It was recommended to first clean the charcoal canister, and if that didn’t work, to replace the entire evaporative control valve assembly. The underbody design of this generation of BMW SUVs does tend to accumulate dust easily. During every maintenance service, remember to ask the technician to blow out the vent pipes—preventing this issue is much simpler than repairing it.
