Variable Intake Manifold, Checking

Variable Intake Manifold, Checking

• Only perform this test if there is a loss of torque. That means elasticity or engine torque is reduced.

Special tools, testers and auxiliary items required

• Hand Vacuum Pump (VAS 6213)

Test Conditions:

• The intake manifold runner control valve (N316) was tested using the vehicle diagnostic tester and is OK.

Test Sequence:

• Fuel rail overview. Refer to => [ Fuel Rail Overview ] Fuel Rail Overview.

- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.

- Start the engine and let run at idle.

- Have a 2nd person increase the engine speed abruptly (press the accelerator pedal).

- Observe the variable intake manifold vacuum actuator.

• The vacuum 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.

- Make sure the vacuum hoses are not porous.

- Disconnect the vacuum hose - 1 - leading to the vacuum actuator for the variable intake manifold on the intake manifold runner control valve - 2 -.






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






- Connect the hand vacuum pump (VAS 6213) to the vacuum actuator for the variable intake manifold.






- Operate the hand vacuum pump (VAS 6213) several times.

• The vacuum actuator must move - arrows -.

If the vacuum actuator does not move:

- Replace the vacuum actuator.