Ford Transit 2002 Owner's Manual page 836

Through electronic recognition of the time of closing, the pump control unit receives exact
information about the start of supply.
The fuel supply measurement occurs between start of supply and end of control of the high
pressure valve and is described as supply period and supply quantity.
Filling
The axial piston is moving backwards. The high pressure solenoid valve and therefore the
supply channel are open.
Because of the pump pressure and the suction effect of the axial piston, the fuel passes
into the high pressure chamber.
Supply
The axial piston is moving forwards, the control slot is opened.
At this moment no fuel is supplied, because the high-pressure solenoid valve is still not
activated by the pump control unit (situation as in illustration "C", only that the axial
piston is not so far advanced).
At a moment determined by the pump control unit, the high pressure solenoid valve is
closed and the needle valve closes the supply channel.
The moment at which the needle valve closes defines the instant which is described as
start of supply. From this time the pressure begins to rise within the high pressure
system.
End of supply
The axial piston is still moving forwards, the control slot is opened more.
At a moment determined by the pump control unit, the high pressure solenoid valve is
opened again and the needle valve opens the supply channel.
The fuel which is still being supplied by the axial piston can return into the pump housing
through the return channel.
To stop the engine, creation of high pressure is completely interrupted (injection quantity
= 0), so that an additional cut-off valve is not provided.
Rotational angle sensor in the distribution injection pump VP 30
Item Part Number
1 -
The rotational angle sensor rotates on a bearing ring which is rigidly linked to the roller ring
and the injection regulator.
The rotational angle sensor is located on a rotating mounting because it needs to generate
its signal relative to the angular position of the roller ring.
Description
Rotational angle sensor
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