Volkswagen Touareg (2003 year). Manual - part 29

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-.

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gles to direction of flow).

– Connect pressure tester -V.A.G 1318- with adapter -

V.A.G 1318/7- , adapter -V.A.G 1318/13- and adapter -

V.A.G 1318/24- as shown.

Note

Ensure that fuel supply line connection engages audibly when

joined.

– Connect remote control -V.A.G 1348/3 A- with adapter -

V.A.G 1348/3-3- to connection -arrow- of fuel pump relay for

left 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:
– Left fuel pump is defective. Renew left fuel delivery unit

⇒ page 102

 .

– Open lever of pressure tester and let fuel flow back to fuel tank

through hose -V.A.G 1318/13- .

– Remove pressure tester -V.A.G 1318- with adapters.

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Electronic power control (EPC)

1 - Bearing bracket

❑ Removing and instal‐

ling: ⇒  Brake systems;

Rep. gr.  46 ; Assembly

overview - brake pedal

(LHD) .

2 - Connector

❑ Black, 6-pin.

3 - 10 Nm
4 - Accelerator position sender

-G79- and accelerator position

sender 2 -G185-

❑ Not adjustable.
❑ Remove footwell cover

to remove sender.

Function of EPC system
The position of the accelerator is transmitted to the engine control

unit by two accelerator position senders (variable resistors to‐

gether in one housing) connected to the accelerator.
The position of the accelerator (driver's requirement) is a main

input value for the engine control unit.
The throttle valve is operated over the complete engine speed

and load range by an electric motor (throttle valve positioner) in

the throttle valve module.
The throttle valve is operated by the throttle valve positioner which

is controlled by the engine control unit.
When the engine is not running and the ignition is switched on,

the engine control unit moves the throttle valve exactly as pre‐

scribed by the accelerator position sender. That is, when the

accelerator is depressed halfway, the throttle valve positioner

opens the throttle valve by the same amount. The throttle is then

approximately half open.

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115

can open or close the throttle valve independently of the accel‐

erator position sender.
This means that the throttle valve can already be completely open

even though the accelerator is only depressed half way. This has

the advantage of preventing throttling losses at the throttle valve.
This also results in significantly improved consumption and ex‐

haust emission values under certain load conditions.
The torque required by the engine can be produced by the engine

control unit by optimising the combination of throttle valve cross-

section and charge pressure.
After evaluating the torque requirements of various components

(e.g. air conditioning system, automatic gearbox, ABS/ESP and

so on), the engine control unit calculates the optimal throttle valve

opening angle for the respective situation.
Observe safety precautions.
Observe rules for cleanliness.

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