Injection Cycle; High-Pressure Chamber Fills - Volkswagen 1.9-Liter TDI Owner's Manual

Injection Cycle

High-Pressure Chamber Fills

During the filling phase, the pump piston
moves upward under the force of the
piston spring and thus increases the
volume of the high-pressure chamber.
The pump/injector solenoid valve is
not activated.
Roller-Type
Rocker Arm
Injection Cam
High-Pressure
Chamber
Pump Injection System
The solenoid valve needle is in its
resting position.
The path is open from the fuel supply line
to the high-pressure chamber.
The fuel pressure in the supply line
causes the fuel to flow into the
high-pressure chamber.
Pump Piston
Piston Spring
Solenoid
Valve Needle
Pump/Injector
Solenoid Valve
Fuel Return Line
Fuel Supply Line
Injector Needle
SSP209/024
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