Intake Manifold Change-Over, Checking

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

Special tools and workshop equipment required 

• Hand Vacuum Pump: VAS6213 
  Fig 1: Hand Vacuum Pump VAS 6213

  Courtesy of AUDI OF AMERICA, LLC

Test Conditions 

• The Intake Manifold Runner Control Valve -N316- was checked with a Vehicle Diagnostic Tester.

If the Intake Manifold Runner Control Valve -N316- is OK, perform the following tests:

-- Remove the engine cover. Refer to ENGINE COVER, REMOVING AND INSTALLING .

-- Start engine and let run at idle.

-- Have a second technician increase the engine speed abruptly (press accelerator pedal). Watch the vacuum actuator for the intake manifold change-over.

• The linkage -1- from the adjusting element for the intake manifold flap must tighten in direction of -arrow-.

  Courtesy of AUDI OF AMERICA, LLC

If change over does not function as specified:

-- Check the vacuum system for leaks.

-- Check the vacuum lines for correct connection.

-- Check that the vacuum hoses are not porous.

-- Set the slide ring -1- on the Hand Vacuum Pump: VAS6213  to position -A- for "vacuum".

-- Connect the Hand Vacuum Pump: VAS6213  to the actuator for the Intake Manifold Runner Control Valve -N316-.

Courtesy of AUDI OF AMERICA, LLC

-- Operate the Hand Vacuum Pump: VAS6213  several times.

• The linkage -1- from the adjusting element for the intake manifold flap must tighten.

-- Discharge the vacuum.

• The linkage returns to the starting position.
• The linkage must move in both directions of -arrows-.

-- If the linkage does not move, replace the intake manifold.