Generic Scan Tool

Variable Intake Manifold, Checking

Only perform the test if there is a loss of torque. That means there is a reduction in the engine acceleration.

Special tools, testers and auxiliary items required

• Hand Vacuum Pump (VAS 6213)

Test Conditions

• The intake manifold runner control valve (N316) was checked with a vehicle diagnosis tester.

If the intake manifold runner control valve is OK, perform the following tests:

- Remove the engine cover.

- Start the engine and let it run at idle.

- Have a second person increase engine speed abruptly (press accelerator pedal). Observe the variable intake manifold vacuum actuator.

• The actuator must activate - arrow -.






If the change-over does not function as specified:

- Check the vacuum system for leaks.

- Check whether the change-over mechanism moves easily. Do this by actuating the linkage by hand.

- Check whether the vacuum lines are correctly connected.

- Check that vacuum hoses are not porous.

- Remove the adjusting element vacuum hose - 1 - for the intake manifold runner control valve from the control valve actuator - 2 -.






- Set the slide ring - 1 - on the (VAS 6213) to the -A- position for "vacuum."






- Connect the (VAS 6213) to the intake manifold runner control valve actuator.






- Operate the (VAS 6213) several times.

The vacuum actuator must move - arrows -.

- Replace the vacuum actuator if it does not move.