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Home >> Volkswagen >> 2022 >> Passat R-Line >> Repair and Diagnosis >> Engine Performance >> Fuel Delivery >> Fuel Supply [CBTA,CBUA,CDVB,CPKA,CPRA,CCCA,DDSA,DDSB] >> 20 Fuel Supply >> EVAP System >> Fuel System, Checking For Leaks >> Fuel System Leak Detection
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Fuel System Leak Detection

Test Conditions:

-- Connect the : KLI9210  to the vehicle battery.

-- Remove right rear wheel housing liner.

-- Remove the hose to the air filter -arrow- from the Leak Detection Pump -V144-.

Fig 2: Identifying Air Filter Hose
GWWN20-10914Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Close the connection on the Leak Detection Pump -V144- with a plug -A-.

Fig 3: Identifying Plug
GWWN20-10915Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Set the valve -D- to "Test". The fuel system is now filled.

Fig 4: Checking Evaporative Emissions Tester KLI 9210 DLX To Determine Whether There Is Enough Fluid In Smoke Generator
GWWN20-10395Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Watch the pressure gauge -C- and the flow meter -E-. The fuel system is filled if the flow rate decreases and the pressure increases to 10 in. H2O (25 mbar).

-- After the pressure has stabilized, set the valve -D- to "Hold".

If the Pressure Drops or If No Pressure Develops, Then Locate the Leak as Follows:

-- Set the valve -D- to "Test" and fill the system with smoke.

-- While the fuel system is being filled, press the smoke generator button -I- for approximately one minute.

The fuel system is now under pressure and filled with smoke.

-- Check all the lines, hoses and the fuel filler cap for escaping smoke.

NOTE:

Illuminate components and hoses with a strong flood light, the smoke will be more visible.

An ultrasonic sensor tester or commercially available leak spray can also be used to locate leaks.

Depending on how long fault finding lasts, the smoke generator button may need to be pressed again. This ensures there is enough smoke present in the fuel system.

The installation opening inside the passenger compartment must be opened to check the flange on the fuel pump and fuel filter.

Fig 5: Identifying Fuel Delivery Unit Cover
GWWM20-0233Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Replace any leaking hoses or components.

After completing the work, perform the "Check tank ventilation system for leaks" guided function with the Vehicle Diagnostic Tester.