A BMW 523Li sedan equipped with an N52 engine stalled at low speed. The engine was restarted and started smoothly.
Fault diagnosis:
1) Perform diagnostic instrument detection, the fault code is 1F0525—–
Internal fault of the engine control module, relative fuel quality credibility monitoring error.
2) Clear the fault code, the fault remains.
3) Check the fuel tank and fuel supply system components, normal.
4) Considering that the fault occurs in the intake system, check the air filter and find that the air filter is not installed properly and leaks.
Fault analysis: The air filter is not installed properly, resulting in the engine control module inaccurate calculation of the intake flow sensor when the vehicle is driving at low speed, and the engine often stalls.
Troubleshooting: Install the air filter and eliminate the fault.