Volkswagen Amarok 2011, Workshop Manual

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– Release clip -2- and detach fuel pressurisation line -3- from
high-pressure pump -1-. Collect escaping fuel with a cloth.
– Connect pressure tester -VAS 6550- to fuel supply line with
adapter -VAS 6550/1- and -VAS 6550/2- .
– Make sure that drain tap is closed and cut-off taps are open.
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
– Read off fuel pressure on pressure gauge.
• Specification: 4.0…7.0 bar
Fuel pressure OK, check holding pressure
⇒ page 165 .
If the specification is exceeded:
– Pressure limiting valve in fuel delivery unit is defective.
Note
The pressure limiting valve is integrated in the fuel delivery unit
and cannot be renewed separately.
If the specification is not attained:
– Fuel pump is defective, renew fuel delivery unit
⇒ page 172 .
2.1.3 Checking holding pressure
Test prerequisite
• Fuel pressure OK and pressure tester -VAS 6550- connected.
Check fuel pressure ⇒ page 164 .
Test sequence:
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
– Read off fuel pressure on pressure gauge.
• Specification: 4.0…7.0 bar
– End self-diagnosis and switch ignition off.
– Observe pressure drop on pressure gauge. After 10 minutes,
pressure must not drop below 3.0 bar.
If the pressure drops further:
– Actuate fuel pump with final control diagnosis to build up fuel
pressure.
Amarok 2011 ➤
4-cylinder injection engine (2.0 l direct injection engine, turbocharger) - Edition 02.2011
2. Fuel pump
165