Test sequence

• Remove engine cover.
• Remove intake hose between Mass Air Flow (MAF) sensor and throttle valve control module: → 24 MULTIPORT FUEL INJECTION (MFI)

Fig 1: Locating Vacuum Hose At Combi-Valve

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Pull vacuum hose off Secondary Air Injection (AIR) solenoid valve N112 and combi-valve - arrow  -.

Fig 2: Hand Vacuum Pump VAG 1390 Connected To Vacuum Hose From Combi-Valve

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Connect hand vacuum pump VAG 1390 to vacuum hose from combi-valve - arrow  -.

Fig 3: Locating Pressure Hose To Combi-Valve At Connection

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Disconnect pressure hose to combi-valve at coupling - arrow  - and blow in using light pressure. Combi-valve must be closed.
• Operate hand vacuum pump. Combi-valve must open.

When the combi-valve does not open or is continuously open:

• Replace combi-valve, - -.