LEMON Manuals: Even more car manuals for everyone
Home >> Audi >> 2016 >> S5 Prestige, 2D Convertible >> Repair and Diagnosis >> External Pages >> Different car >> Section 655 (Fuel Supply System - Engine Code(S): CAEB, CALB, CHJA, CPMA, CPMB, CTUC & CTUD) >> 20 Fuel Supply System >> EVAP System >> Leak Detection System >> Tank Leak Diagnosis, Performing, Vehicles Through My 2012

Tank Leak Diagnosis, Performing, Vehicles Through My 2012

WARNING: This page does not describe the selected car, but rather 13 other vehicles, including the 2017 Audi SQ5, 2017 Audi Q5, 2016 Audi SQ5, 2016 Audi Q5, and 2015 Audi SQ5. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostic leak test occurs in "Guided Fault Finding" see Vehicle Diagnostic Tester.

Checking the Fuel Tank System and Tank Ventilation System for Leaks

NOTE:

The following describes individual areas in the fuel supply and ventilation systems where leaks are possible. After repairing a possible leak, perform a leak test to ensure that leak was successfully repaired.

-- Switch off the ignition.

Fig 1: Identifying Fuel Filler Cap (Fuel Cap)
GWWA20-1253Courtesy of AUDI OF AMERICA, LLC

-- Make sure the fuel tank cap -arrow- was closed completely during the test.

-- Check whether seal of fuel filler cap was damaged or crimped. Replace if necessary.

-- Remove the rear bench seat, refer to REAR SEAT, REMOVING AND INSTALLING .

Fig 2: Identifying Locking Flange Cover & Bolts -Arrows-
GWWA20-10514Courtesy of AUDI OF AMERICA, LLC

-- Remove the locking flange cover -1- -arrows-.

NOTE:

Observe installation notes for locking flanges, refer to FUEL DELIVERY UNIT/FUEL LEVEL SENSOR, REMOVING AND INSTALLING .

-- Check sealing rings seals under locking flanges are OK and lock rings are properly tightened on fuel tank. Also check the fuel line connections.

-- Visually check all wires and hose connections of fuel supply system and replace leaking lines, for example:

NOTE:

Leaks at lines and components of tank system can sometimes be located using a nonflammable, environmentally compliant leak detection spray. For this, initiate leak diagnostic several times in sequence to build up pressure in the system. At leaking areas, bubbles will form.

-- Perform a visual inspection on the fuel system components and tank ventilation system:

NOTE:

Due to the form or function of the components, leaking areas may not always be localized by spraying on leak detection spray. In this case, clamp off the relevant component using Hose Clamps - Up To 25mm3094 and initiate tank leak detection diagnostic. If the leak is no longer indicated, the component that was clamped off is defective. If clamped off directly at the leak detection pump and a leak is still indicated, the leak detection pump itself is leaking.