Cooling System, Checking For Leaks

WARNING: This page is about a different car, the 2010 Audi Q7, 2009 Audi Q7, 2008 Audi Q7, and 2007 Audi Q7. However, it is still accessible from the selected car via links, so may be relevant.

Special tools and workshop equipment required

Cooling System TesterVAG1274B
Cooling System Tester - AdapterVAG1274/8
Cooling System Tester - AdapterVAG1274/9

Procedure

Fig 1: Identifying Cooling System Tester VAG 1274 With Adapter VAG 1274/8 On Expansion Tank

Courtesy of AUDI OF AMERICA, LLC

Proceed as follows:

Engine at operating temperature.

WARNING:

Risk of scalding due to hot steam and hot coolant.

The coolant system is under pressure when the engine is warm.
Reduce pressure by covering coolant reservoir cap with a cloth and carefully opening.

-- Open the coolant reservoir cap.

-- Position Cooling System TesterVAG1274B with Cooling System Tester - AdapterVAG1274/8 on the coolant reservoir.

-- Generate approximately 1 bar pressure with cooling system tester hand pump.

-- If pressure falls, search for leaks and correct problem.

Fig 2: Checking Pressure Relief Valve In Coolant Reservoir Cap

Courtesy of AUDI OF AMERICA, LLC

-- Attach the Cooling System TesterVAG1274B with Cooling System Tester - AdapterVAG1274/9 to the cap.

-- Generate pressure with cooling system tester hand pump.

The pressure release valve must open at 1.4 to 1.6 bar.

-- If pressure relief valve does not open as specified, replace cap.