Engine Code AAZ

Special Tools, Testers And Auxiliary Items:
- VAG1397A turbocharger tester

Checking Conditions:
The turbocharger and wastegate are an assembly. A faulty turbocharger must be replaced because it is not possible to repair using workshop equipment.

Requirements for proper turbocharger operation and achieving specified boost pressure:
- No leaks from intake and exhaust systems
- Wastegate control line is not blocked, loose or leaking
- No engine or fuel injection mechanical malfunctions, e.g. start of injection, fuel injectors and compression pressure
- Engine oil temperature 80°C (176°F) minimum

Test Sequence:
- Measure boost pressure under full load, while driving on road.

Test duration per measurement: 10 seconds maximum.





- Disconnect hose (at one end) running between intake manifold -1- and Diesel injection pump -2-.
- Using tee, connect VAG 1397A turbocharger tester.

NOTES:
- To operate the VAG1397A turbocharger tester see manufacturers operating instructions.
- If boost pressure is being measured while driving, a second person must be used to read and operate the turbocharger tester.
- Make sure that the pressure hose is not trapped between the hood and the body.

- Measure boost pressure at wide open throttle.
While driving on an open road:
- In 2nd gear (manual) or with transmission range selector lever in position 1 (automatic).
- While simultaneously applying brakes to maintain approx. 37 MPH (60 kph).

Specification: 0.60 to 0.83 bar (relative pressure).

If specification not obtained:
- Replace turbocharger.

If the boost pressure is too high and if the wastegate control line is not blocked, loose or leaking:
- Replace turbocharger (wastegate is faulty and unit can only be replaced as an assembly).