Combination Valve, Checking For Function And Leaks

Special tools and workshop equipment required 

• Hand Vacuum Pump VAS6213

Procedure 

Fig 1: Engine Cover

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

-- Remove the engine covers -1 and 2- upward.

Versions with Two Secondary Air Injection Solenoid Valve -N112-.

Fig 2: Identifying Vacuum Hose -2-

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

Versions with A Secondary Air Injection Solenoid Valve -N112-.

Fig 3: Secondary Air Injection Solenoid Valve Vacuum Hose & T-Connection

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-- Follow the routing of the vacuum hose -1- from Secondary Air Injection Solenoid Valve -N112- until the T-connection -2- down.

-- Remove the vacuum hose -arrow- for the combination valve to be checked from the T-connection -2-.

Continuation for All

Fig 4: Identifying Front Air Hose -Arrow

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-- Connect the Hand Vacuum Pump VAS6213 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 (AIR) hose using light pressure (do not use compressed air).

• The AIR 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 AIR combination valve does not open, replace it: left refer to LEFT COMBINATION VALVE, REMOVING AND INSTALLING , right refer to RIGHT COMBINATION VALVE, REMOVING AND INSTALLING .

Assembling

Assemble in reverse order of disassembling. Note the following: