Air Injection Vacuum Control Solenoid Valve: Service and Repair

Secondary Air Injection Combination Valves, Checking

Special tools, testers and auxiliary items required

• Hand Vacuum Pump (VAS 6213) or Hand Vacuum Pump (V.A.G 1390)

Conditions

• The Secondary Air Injection (AIR) solenoid valve (N112) or AIR solenoid valve 2 (N320) was checked with "Guided Fault Finding" in the vehicle diagnostic tester.

Sequence

If the AIR solenoid valve (N112) and AIR solenoid valve 2 (N320) are OK:

- Check whether the vacuum system, including the vacuum reservoir in the intake manifold, is properly sealed.

- Check whether the vacuum lines are correctly connected.

- Check that vacuum hoses are not porous.

If no malfunction was found:

- Disconnect the secondary air hose at position indicated by - arrow -.





- Lightly blow into the hose to the combination valve. Do not used compressed air.

• Both combination valves must be closed, it must not be possible to blow through hose.

If the combination valves are sealed, continue the test.

If it is possible to blow air through, check which combination valve is open:

- Seal the hose leading to right combination valve - arrow - using a hose clamp.





- Lightly blow again into the hose to the combination valve. Do not used compressed air.

If it is still possible to blow air through, then the left combination valve is not sealed. If it is now no longer possible to blow air through it, then the right combination valve is not sealed.

- Remove the vacuum hose from the combination valve.

- Connect the (VAS 6213) to the left combination valve.





- Operate (VAS 6213) several times.

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

If the combination valve does not open:

- Replace the left combination valve.

- Repeat the test on the right combination valve.