Fuel Rail: Description and Operation

Fuel Rail

Three fuel injectors are installed in each inlet manifold and connected to the fuel rail. The injectors are sealed in the fuel rail and the inlet manifolds by 'O' ring seals. A quick release coupling connects the feed pipe from the fuel tank to the fuel rail.

An accumulator is attached to the fuel rail, to damp out pressure pulses from the pump and ensure that the pressure in the fuel rail is constant. On all except NAS vehicles, a vacuum pipe connects the accumulator to the inlet manifold to aid the damping process.

A Schraeder valve is installed in the 'fuel return' pipe (on all except NAS vehicles) or above the accumulator (on NAS vehicles) to provide a pressure test connection for maintenance.