Inlet Phase

Courtesy of VOLVO CARS CORPORATION

1. Control valve, fuel flow
2. Piston
3. Outlet valve

The piston (2) moves down through the spring. The area above the piston increases in volume, whereupon, by the fuel pump in the tank, the pressurized fuel flows in through the open control valve (1). The outlet valve (3) is closed. The control valve, fuel flow, consists of an electric coil that axially moves a bar, which, in turn, affects a valve. No power when the valve is open. When the engine control module (ECM) powers the coil, the valve closes.