Combination Valve, Checking

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Special Tools And Workshop Equipment Required

Hand Vacuum Pump VAS 6213

Procedure

Vacuum lines and hose connections free of leaks.
Vacuum lines not plugged.

-- Remove the vacuum hose -1- or -2- on the combination valve being checked.

NOTE:

The hose to the right combination valve is shown in the illustration.

Fig 1: Identifying Combination Valve Vacuum Hoses

Courtesy of AUDI OF AMERICA, LLC

-- Connect the Hand Vacuum Pump VAS 6213 to the vacuum hose for the combination valve to be checked.

-- Remove the front secondary air hose -arrow- from its bracket and disconnect it; do to so press the release buttons.

-- Blow into the secondary air injection hose using light pressure (do not use compressed air). Lengthen the secondary air injection hose with an extension hose, if necessary.

The secondary air injection combination valves must be closed. It must not be possible to blow through.

-- Operate hand vacuum pump.

The relevant combination valve must open, it must be possible to blow through.

-- If the secondary air combination valve does not open, replace it, refer to COMBINATION VALVE, REMOVING AND INSTALLING .

Assembling

Assembly is performed in the reverse order of disassembly, noting the following:

NOTE:

Replace the O-ring.