4BD1 4BD1T 4BD1-T oil pump 8-94114491-1 8941144911 L210-0004S for ISUZU Parts The function of the fuel pump is to suck the fuel out of the fuel tank, pressurize it and transport it to the fuel supply pipe, and cooperate with the fuel pressure regulator to establish a certain fuel pressure. Our products are according to the standard of OEM to manufacture.