What we usually refer to as automobile oil roads usually include two types: motor oil road and gasoline road. The oil circuit refers to the path inside the engine through which the oil runs through the oil pump. Gasoline is also called fuel system, which refers to the pipeline between car fuel and the combustion chamber of the engine.
The oil circuit in this article refers to the latter, which is the fuel system of the car. It includes: fuel filter, gasoline pump, fuel pressure regulating valve, gasoline pipeline, carbon canister, and fuel injector.