Volkswagen Touareg (2003 year). Manual - part 32

in smoke generator.

– Set valve -D- to „Hold“.
– Open nitrogen bottle -H-.
– Connect test hose -G- to self-test connection -B-.
– Set valve -D- to „Test“.
– Regulate pressure to 25 mbar (10 in. H2O) with pressure re‐

ducer -J-.

– Set valve -D- to „Hold“.
– Now pressure must be maintained for at least 2 minutes.

Check tester if pressure is not maintained.

Checking fuel system for leaks:

– Pull off rear engine cover -arrows-.

– In engine compartment, disconnect breather line -arrow- to

activated charcoal filter solenoid valve 1 -N80- .

– Connect adapter hose -KLI 9210/55-2- between activated

charcoal filter solenoid valve 1 -N80- and breather line -A- as

shown in illustration.

– Connect measuring hose -G- from fuel system tester -KLI

9210- to adapter hose -KLI 9210/55-2- .

– Connect fuel system tester -KLI 9210- to vehicle battery.

Touareg 2003 ➤

4. Activated charcoal filter system (vehicles for USA and Canada)    

125

OBD

.

– Now select diagnostic mode 8 „Tank leak test“.
– Select entry „Tank leak test“ and press right arrow button 

►

 to

initiate test.

Note

♦

Once the diagnostic mode 8 „Tank leak test“ has been acti‐

vated, the leak diagnostic pump and the activated charcoal

filter solenoid valve 2 -N115- are closed for max. 1,000 sec‐

onds. The activated charcoal filter solenoid valve 1 -N80- is

not activated. Now the entire system is closed.

♦

If the engine control unit cancels the test, it is possible to ini‐

tiate it again by switching off and restarting the engine.

– Set valve -D- to „Test“. The fuel system will now be filled with

nitrogen.

– Observe pressure gauge -C- and flow meter -E-. When the

throughput quantity decreases and the pressure increases to

25 mbar (10 in. H2O), the fuel system is filled.

Note

Depending on the filling level of the fuel tank, this process can

take up to 3 minutes.

– Once pressure has stabilised, set valve -D- to „Hold“.
• After 5 minutes the pressure must not drop below 20 mbar

(8 in. H2O).

If pressure does not drop, exit from diagnostic mode 8 and check

if fuel system diagnostic pump -V144- can build up pressure

⇒ page 129

 .

If no pressure builds up or the pressure is not held for at least 5

minutes, localise leak as follows:
Leave engine running at idling speed for at least 8 minutes with

activated diagnostic mode 8.

– First check activated charcoal filter solenoid valve 1 -N80- for

leaks. To do this, clamp off hose to activated charcoal filter

solenoid valve 1 -N80- using a hose clip -arrow-. Also refer to

⇒ Item A (page 128)

 .

Touareg 2003 ➤

126

put quantity decreases and the pressure increases to 25 mbar

(10 in. H2O), the fuel system is filled.

– Once pressure has stabilised, set valve -D- to „Hold“.
– If the pressure does not drop again, renew activated charcoal

filter solenoid valve 1 -N80- .

If pressure still drops:
– Set valve -D- again to „Test“.
– While fuel system is being filled, press button -I- for smoke

generator for approx. one minute.

The fuel system is now pressurised and filled with smoke.
– Check whether smoke escapes from any visible fuel system

line or hose. Also check fuel tank cap.

Note

♦

Light up the components and hoses with a strong floodlight. In

the floodlight, smoke is more visible.

♦

For leak detection in accessible areas, also use ultrasonic de‐

tector or commercially available leak detecting spray.

♦

Depending on how long the fault finding takes, it may be nec‐

essary to press the smoke generator button from time to time.

This ensures that sufficient smoke is present in the fuel sys‐

tem.

If no fault is found:
– Remove rear right wheel housing liner.
If smoke escapes from air filter 

⇒ Item 7 (page 128)

 :

– Clamp off hose between activated charcoal filter solenoid

valve 2 -N115- and air filter -arrow-. Also refer to

⇒ Item B (page 128)

 .

– Observe air filter. If smoke no longer escapes, activated char‐

coal filter solenoid valve 2 -N115- is leaking. Renew activated

charcoal filter system solenoid valve 2 -N115- .

Touareg 2003 ➤

4. Activated charcoal filter system (vehicles for USA and Canada)    

127

and air filter -arrow-. Also refer to 

⇒ Item C (page 128)

 .

– Observe air filter. If smoke no longer escapes, shut-off valve

in fuel system diagnostic pump -V144- is leaking. Renew fuel

system diagnostic pump -V144- .

If no smoke escapes from air filter 

⇒ Item 7 (page 128)

 :

– Check whether smoke escapes from any fuel system compo‐

nent or hose.

To inspect flanges for fuel pump and fuel filter, open assembly

openings in vehicle interior.
– Renew leaking hoses or components.
After completing work, perform guided function „checking fuel

tank breather system for leaks“ using ⇒ Vehicle diagnostic tester.

4.2.1

Overview of activated charcoal filter system

1 - Activated charcoal filter
2 - Location of adapter hose -

KLI 9210/55-2-

❑ For leak detection in fuel

system

3 - Activated charcoal filter sol‐

enoid valve 1 -N80-
4 - Breather line

❑ To intake manifold.

5 - Solenoid valve

❑ For fuel system diag‐

nostic pump -V144-

6 - Vacuum line

❑ To intake manifold.

7 - Air filter

❑ For fuel system diag‐

nostic pump -V144-

8 - Fuel system diagnostic

pump -V144-
9 - Fuel tank
10 - Cap
11 - Activated charcoal filter

solenoid valve 2 -N115-
12 - Pressure retention valve
A - Clamp off in this area

❑ For leak detection in fuel

system

❑ For checking activated

charcoal filter solenoid

valve 1 -N80- .

B - Clamp off in this area

❑ For leak detection in fuel system
❑ For checking activated charcoal filter solenoid valve 2 -N115- .

Touareg 2003 ➤

128