Schematic Overview Of Activated Charcoal Filter System - Volkswagen CC 2012 Workshop Manual

– Clamp off hose between fuel system diagnostic pump - V144-
and air filter -arrow-.
– Set valve -D- to "Test".
– Observe pressure gauge -C- and flow meter -E-. When flow
rate decreases and pressure increases to 10 in. H2O
(25 mbar), fuel system is filled.
– Once the pressure has stabilised, set valve -D- to "Hold".
• After 5 minutes, pressure must not drop below 8 in. H2O (20
mbar).
– If pressure no longer drops, renew fuel system diagnostic
pump - V144- .
If the pressure is not held for at least 5 minutes or does not build
up, localise leak as follows:
– Fill fuel system with smoke. To do this, set valve -D- to "Test"
again.
– While fuel system is being filled, depress button -I- for smoke
generator for approx. one minute.
The fuel system is now pressurised and filled with smoke.
– Check all pipes and hoses of fuel system for escaping smoke.
Also check fuel tank filler cap.
Note
Illuminate all components and hoses with a powerful light. This
♦
will make the smoke easier to detect.
For leak detection in accessible areas, use ultrasonic tester 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.
To inspect flanges for fuel pump and fuel filter, assembly
♦
opening in vehicle interior must be opened ⇒ Vehicle diag‐
nostic tester.
– Renew leaking hoses or components.
After completing work with vehicle diagnostic tester , perform gui‐
ded function "Checking fuel tank ventilation system for leaks".
5.3.3

Schematic overview of activated charcoal filter system

CC 2012 ➤ , Passat 2011 ➤ , Passat Variant 2011 ➤
Fuel supply system, petrol engines - Edition 05.2019
5. Activated charcoal filter with fuel tank leak detection
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