Operation CHARM: Car repair manuals for everyone.

Combination Valve, Checking



Combination valves, checking

Recommended special tools and equipment
- VAG1390 Hand Vacuum Pump

Test requirements
- No leaks in vacuum lines or hose connections.
- Vacuum hoses not clogged or kinked
- Pressure hose for Secondary Air Injection (AIR) Pump Motor not clogged or kinked

Test sequence
- Disconnect vacuum hose of combination valve to be checked:
- Cylinder bank 1, item 3 ,
- Cylinder bank 2, item 4 .


NOTE:
- Cylinder bank 1 = in driving direction, right
- Cylinder bank 2 = in driving direction, left


- Connect hand vacuum pump to vacuum connection of combination valve (arrow).


NOTE: Do not use pressurized air for the following test!


- Remove front noise insulation.







- Disconnect pressure hose (arrow) between Secondary Air Injection (AIR) Pump Motor and connecting line and blow into it with light pressure.
Both combination valves must be closed.


NOTE: To disengage, compress the buttons at the hose coupling.


- Operate hand vacuum pump.
The respective combination valve must open.

If the combination valve does not open or it is constantly open:
- Replace the respective combination valve:
- Cylinder bank 1, item 3 ,
- Cylinder bank 2, item 4 .

- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes