Audi Workshop Service and Repair Manuals > A1 > Power unit | 4-cylinder direct petrol injection engine (1.4 ltr. 4-valve turbo), mechanics | Exhaust turbocharger, G-charger | Charge air cooler

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

–	Release hose clips -1 and 2- and remove air hose -arrow-.

Note

Disregard -item 3-.

–	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.

t	Hose connections and air pipes and hoses must be free of oil and grease before assembly.

t	Secure all hose connections with the correct type of hose clips (same as original equipment) → Electronic parts catalogue.

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