PIAGGIO 500 cc Service Manual page 162

Fuel injection
Proceed with the system
The pressure is lower
seal control
Carefully check the tension with the
Activate the pump for 30 seconds using
pump under pressure.
diagnosis tester 020460Y.
If tension is greater than 12 V replace
After the pump stops wait
the pump (see page 9-54 overhaul of
for 3 minutes.
the pump support).
Check the system pressure.
Fuel pressure = greater than 200 KPa
NO
(2 BAR)
Repeat the test. When the pump stops, using long,
flat-tonged pliers, squeeze the return duct acting
YES
only on the extention of the special tool. This action
leads to an increase in fuel pressure.
System seal is good.
Check if the pressure reduces at the same rate as when the system is not squeezed.
The pressure reduces much more slowly
Replace the pressure regulator (see page 9-54
overhaul of the pump support).
Check system seal again
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