Low Pressure-Vacuum Diaphragm, Adjusting

WARNING: This page is about a different car, the 2015 Audi A7 Quattro and 2014 Audi A7 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The adjustment only applies to a new vacuum diaphragm.

Special tools and workshop equipment required

Dial Gauge Holder VW387
Turbocharger Tester Kit VAG1397A
Hand Vacuum Pump VAS6213
Dial Gauge Set VAS6341
Pressure Control Valve VAS6342

Procedure

NOTE:

Follow all the rules of cleanliness, refer to CLEAN WORKING CONDITIONS .

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

-- Secure the Dial Gauge Holder VW387 with the catalytic converter nut -arrow-.

Fig 1: Low Pressure-Vacuum Diaphragm Adjusting

Courtesy of AUDI OF AMERICA, LLC

-- Secure the Dial Gauge Set - Dial Gauge VAS6341/1 with a Dial Gauge Set - Flat Pickup VAS6341/4 on the Dial Gauge Holder VW387.

-- Align the dial gauge with the vacuum diaphragm actuator rod.

-- Adjust the dial gauge 20 to 25 mm pretension.

-- Hand Vacuum Pump VAS6213 and Pressure Control Valve VAS6342 to the vacuum diaphragm -arrow- and to connection "II" on the Turbocharger Tester Kit VAG1397A, as illustrated.

Fig 2: Vacuum Pump Setup

Courtesy of AUDI OF AMERICA, LLC

-- Connect the Pressure Control Valve VAS6342.

The lever -1- is horizontal.

-- Set the Vacuum Pump VAS6213 slide ring in the "vacuum" position.

-- Switch the Turbocharger Tester Kit VAG1397A and set the slide switch to position "II".

-- Check dial gauge for ease of movement.

-- Operate the Hand Vacuum Pump VAS6213 until the Turbocharger Tester Kit VAG1397A shows the following value:

580 ± 5 mbar (8.4 ±.07 psi).

NOTE:

The Turbocharger Tester Kit VAG1397A cannot display values over 580 mbar (8.4 psi).

-- Set dial gauge to "0".

-- Note the measured value.

-- Lower the vacuum via the Pressure Control Valve VAS6342.

440 mbar (6.4 psi)

NOTE:

If the vacuum was reduced too much, raise the vacuum back to 580 mbar (8.4 psi) and adjust again by reducing it.

The actuator rod must have moved opposite the previously measured value 0.8 to 1.2 mm in the direction of the dial gauge.

-- Lower the vacuum via the Pressure Control Valve VAS6342.

100 mbar (1.4 psi)
The actuator rod must have moved opposite the previously measured value 7 to 9.5 mm in the direction of the dial gauge.

-- If the specified value is not reached open the lock nut -1-.

Fig 3: Identifying Lock Nut 1

Courtesy of AUDI OF AMERICA, LLC

-- Remove the lock washer -3- and remove the actuator rod -2- from the mounting pins.

-- Extend or shorten the front part of the actuator rod by turning left or right.

-- Install the actuator rod -2- on the mounting pins.

-- repeat the test with the Hand Vacuum Pump VAS6213 and the Dial Gauge Set - Dial Gauge VAS6341/1.

-- If the specified value is now reached, install the lock washer and tighten the lock nut.