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Home >> Audi >> 2017 >> A6 Premium Plus >> Repair and Diagnosis (Single Page) >> Engine Mechanical >> Fuel System >> Fuel System (EVAP Leak Tester - General Information) >> 20 Fuel Supply >> Fuel System EVAP Leak Test >> EVAP System Leak Test, Vehicles With Fuel Tank Leak Detection Control Module (NVLD) >> Fuel Cap (If Equipped), Testing
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Fuel Cap (If Equipped), Testing

NOTE:

Beginning With MY 2016  , some NVLD Equipped Vehicles Come With A Capless Fuel Fill System. This Means That A Removable Fuel Cap Is Not Part Of The Vehicle Fuel Fill System.

Vehicles With Capless Fuel Fill System 

If A Leak Is Suspected At The Capless Fuel Filler, Employ The Use Of The Smoke Generator. Refer to METHOD 1: LOCATE LEAK WITH SMOKE GENERATOR .

Vehicles With Removable Fuel Cap 

-- Connect fuel cap tester to hose.

-- Screw fuel cap tightly to cap receiver -arrow-.

GWWUS20-A163Courtesy of AUDI OF AMERICA, LLC

-- Turn control valve to "Test".

-- Read flow meter on tester.

If No Flow Is Indicated: 

-- Proceed to Leak Detection Pump -V144-, TESTING FOR INTERNAL LEAKS .

If Flow Is Indicated: 

-- Replace fuel cap and re-test.

If New Fuel Cap Shows No Flow: 

-- Repeat leak test, with new fuel cap installed, using Vehicle Diagnostic Tester in "Basic Settings" mode.

If Leak Test Shows 'System OK": 

-- Perform quality check and return vehicle to customer.