Checking Non-Return Valve Of Left Pump - Volkswagen Touareg 2003 Workshop Repair Manual

– Now connect remote control -V.A.G 1348/3A- with adapter -
V.A.G 1348/3-3- to connection -arrow- of fuel pump relay for
right fuel delivery unit.
– Operate remote control at short intervals until a pressure of
approx. 4 bar has built up.
– Watch pressure drop on pressure gauge. After 10 minutes,
pressure must not drop below 3.0 bar.
If pressure drops:
– Right fuel pump is defective. Renew right fuel delivery unit
⇒ page 102 .
To convert the pressure tester for the left fuel pump:
– Open lever of pressure tester and let fuel flow back to fuel tank
through hose -V.A.G 1318/13- .
1.13

Checking non-return valve of left pump

Test prerequisites
• Remote control -V.A.G 1348/3 A- is still connected.
Note
At the same time, this test checks for leaks in the fuel supply line
connections from the fuel delivery units to the point at which the
pressure tester -V.A.G 1318- is connected.
– Then detach fuel supply hose -2- leading from left fuel delivery
unit from fuel filter -1-.
8-cylinder injection engine - Edition 11.2011
1. Parts of fuel supply system
Touareg 2003 ➤
113