Variable Induction System: Testing and Inspection

Intake Manifold Flap Vacuum Actuator, Checking

The test should only be done if there were complaints about reduced torque, elasticity or engine power.

Special tools, testers and auxiliary items required

• Hand Vacuum Pump (VAS 6213)

Procedure

- Start engine.

- Accelerate abruptly and observe linkage on back side of vacuum actuator when doing so.

• Linkage must move - arrow -.





If the linkage on the vacuum actuator does not move, check:

• the vacuum system for leaks.

• the change-over mechanism linkage for ease of movement.

• the vacuum lines for correct connection.

• the vacuum hoses.

If no malfunction can be found:

- Remove air filter housing. Refer to => [ Air Filter Housing ] Air Filter Housing.

- Disconnect vacuum hose - 3 - on vacuum actuator.





• Ignore - 1 and 2 - and - arrows -.

- Connect Hand Vacuum Pump (VAS 6213) to vacuum actuator connector as shown in illustration.





- Generate vacuum using hand vacuum pump.

- Observe linkage on vacuum actuator when doing so:

• Linkage must move - arrow -.





- Vent the hand vacuum pump.

• Linkage must move back into output position.

• Check linkage movement sequence over entire adjustment range: it must move continuously without jerking.

If the linkage on the vacuum actuator does not move or moves with a jerk:

- Replace vacuum actuator. Refer to => [ Intake Manifold Flap Vacuum Actuator ] Service and Repair.