Audi Workshop Service and Repair Manuals

Checking charge air system for leaks Special tools and workshop equipment required

t  Charge air system tester -V.A.G 1687- with adapters -V.A.G 1687/10- and -V.A.G 1687/14-

t  Hose clip pliers -VAS 6362-

Procedure –  Pull off engine cover panel (front) -arrows- and remove towards front.

–  Remove air cleaner housing → Rep. gr.24. –  Plug vacuum hose -3-.

–  When performing test, fit screw-type hose clips from charge air system tester -V.A.G 1687- in place of spring-type clips -arrows-.

–  Connect adapter -V.A.G 1687/10- with -V.A.G 1687/14- to turbocharger. –  Connect hose -1- of charge air system tester -V.A.G 1687- to adapter.

Prepare charge air system tester -V.A.G 1687- as follows: –  Unscrew pressure control valve -2- completely and close valves -3- and -4-. l  Make sure knob is pulled out before turning pressure control valve. –  Using a commercially available connection piece, connect charge air system tester -V.A.G 1687- to compressed air -1-.   Note If there is water in sight glass, remove drain plug -6- and drain water. –  Open valve -3-.   Caution Risk of damage if pressure is set too high. The pressure must not exceed 0.5 bar. –  Adjust pressure to 0.5 bar via pressure control valve -2-. –  Open valve -4- and wait until test system is pressurised. If necessary, adjust pressure to 0.5 bar again. –  Check charge air system for audible leaks or leaks that can be felt with the hand; apply commercially available leak detecting spray or use ultrasonic tester -V.A.G 1842-.   Note t  A small amount of air escapes through the valves and enters the engine. Therefore it is not possible to perform a pressure retention test. t  For operation of ultrasonic tester -V.A.G 1842-, refer to → Operating instructions. t  Release pressure in test circuit by detaching hose coupling from adapter before removing adapter. Assembling –  Install air hoses with screw-type clips → Fig.. –  Remove air cleaner housing → Rep. gr.24.