Parts & Accessories Spare parts Carburetor valve that controls the increase of engine RPM when the AC is turned on. Increases the accelerator pump. Accelerator Pump Increase: The primary function of this valve is to automatically control the engine's RPM increase when the air conditioner is turned on to ensure stable engine performance and prevent it from stalling under additional load. Vacuum Control: It acts as a solenoid valve that opens or closes "suction" or "vacuum" paths based on an electrical signal. ‼‼Fits the following cars: Nissan Datsun: 810 and 310 models. Nissan ZX: 280ZX and 300ZX models (between 1979 - 1989). Nissan Sunny / Stanza: Older models. Other models: Laurel, Silvia, and Bluebird.