Fuel Pump
An electric fuel pump is used to provide fuel pressure of about 60-80 psi (4.1-5.5 kg/cm2 ). To aid in starting, a check valve in the pump works in conjunction with the accumulator and the piston seal in fuel distributor, to maintain pressure in the system when the engine is not running.
The fuel pump is controlled by a relay to prevent it from continuing to operate if the engine stalls. It can be wired in several ways, the most common being through a switch on the air flow sensor or through a coil energized by the ignition system. When testing the system, the safety relay must be by-passed.