The causes of petrol pump failure are: 1. insufficient oil in the fuel tank; 2. poor quality of petrol; 3. long-term failure to replace the petrol filter. The symptoms of car petrol pump failure are: 1, the supply system of fuel collapses, the vehicle cannot be started; 2, no residual pressure, fuel pressure does not reach the specified fuel pressure value, poor atomisation and difficult starting; 3, the engine fault light is on, the engine shakes abnormally.