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Variable Intake Manifold, Checking






Variable Intake Manifold, Checking

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

Special tools, testers and auxiliary items required

Hand Vacuum Pump (VAS 6213)

Test Conditions

The Intake Manifold Runner Control (IMRC) valve (N316) was tested with the vehicle diagnosis tester.

If the IMRC valve is OK, perform the following tests:

- Remove the engine cover carefully.

- Start engine and let run at idle.

- Have a 2nd 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 the vacuum hoses are not porous.

- Remove the adjusting element vacuum hose - 1 - for the IMRC 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 IMRC valve actuator.






- Operate the (VAS 6213) several times.

The vacuum actuator must move - arrows -.

- Replace the vacuum actuator if it does not move.