Cruze showed that the mixture was rich after washing the throttle oil circuit.

The car passed the test, and the fault code showed that the fuel system was too thick, indicating that the car was not fully burned and the mixing ratio was poor. The failure may be due to insufficient oxygen (air) and intake pressure in the cylinder, resulting in insufficient fuel combustion in the cylinder. It is recommended to check whether the spark plug is in good condition, whether the intake pressure is sufficient (intake manifold pressure sensor parameters), whether the throttle valve is clean and whether the three-way catalyst is blocked.