Why does the hot water pipe pass through the throttle valve in the design of automobile engine?

(1) First, the throttle valve is a movable valve to control the combustible mixture to enter the cylinder block, and the combustible mixture needs temperature, pressure and gas uniformity to work in the cylinder block. (2) When the engine is started at low temperature, some combustible gases are not completely burned and discharged from the cylinder with exhaust gas, which wastes resources and pollutes the air, and also affects the low-temperature acceleration of the engine. Therefore, the hot water pipe passing through the throttle allows the engine to heat the throttle in the shortest time when it is started at low temperature, which also improves the fuel utilization rate. (3) The throttle valve is installed on the engine block. After the engine is heated, this hot water pipe also cools the throttle as a whole to ensure the normal operation of the engine.