Brilliance China Jie Jun overhauled the engine and was not idle. What happened?

According to this car, there are many types of engines, which can be summarized as follows:

A. Components that directly affect idle speed: throttle section: such as stepping motor, dirt (to be cleaned during maintenance), stuck valve, etc.

B. Matching after assembly: In case of power failure, relevant components need to be matched again or restored to the initial values.

C. sensors:

1, crankshaft position sensor, whether it is replaced or installed correctly, and whether there is any quality fault in the components.

2. Camshaft sensor.

3. Whether the cooling water temperature or air intake and oil pressure sensors are abnormal.

4, other electronic control (ignition, fuel) sensor parameter inspection.

5. Valve timing.