2. Due to too much carbon and dirt deposited in the air inlet, the cross-sectional area of the air passage changes, resulting in too rich or too thin mixture, which makes the combustion abnormal or the engine shake or even fail to start after starting. Or because there is something wrong with the injector, it leaks or accumulates too much carbon, which leads to too thin mixture at start-up and makes it difficult to start.

3. In addition, if the canister or the canister solenoid valve fails, it will also lead to difficulties in starting.