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Test boost pressure control solenoid valve > < Test boost pressure - engine code AGR

A3 Mk1

Diesel Direct Injection and Glow Plug System (TDI 4 cyl.) >07.99
Testing the boost pressure system
Checking boost pressure for engine codes ALH, AHF
  • ‒ Checking boost pressure The boost pressure is measured with the fault reader V.A.G 1551 during a test drive.
  • ‒ Perform a road test.
Important:
Secure fault reader to the rear seat and operate from this location. For this purpose, always observe the relevant safety precautions => Page 12.
  • ‒ Read measured value block, display group 11, Engine idling
 
→ Indicated on display:
Read measured value block 11    ⇒
    900 rpm    938 mbar    978 mbar    92 %    
  • ‒ Accelerate vehicle in 3rd gear from about 1500 rpm using full throttle.
  • ‒ Press PRINT key on V.A.G 1551 at about 3000 rpm.
     
    → Specification for display zone 3: 1850...2200 mbar
    Read measured value block 11    ⇒
        3090 rpm     1948 mbar    1989 mbar    62 %    

    If measured boost pressure is not OK:

    • ‒ Initiate basic setting "Function 04" and select display group 11
    • ‒ Run engine at idling speed.
     
    → Indicated on display:
    System in basic setting 11    ⇒
        900 rpm    on    969 mbar    0 %    

    This display group is used for checking the boost pressure control. The boost pressure control solenoid valve -N75 opens and closes alternately for periods of 10 seconds.

    System in basic setting 11

    ⇒

    ◂ Indicated on display

    900 rpm

    on

    969 mbar

    0 %

    Boost pressure control solenoid valve actuation

    Boost pressure

    Boost pressure control solenoid valve open

    Engine speed

    System in basic setting 11

    ⇒

    ◂ Indicated on display

    900 rpm

    off

    948 mbar

    99 %

    Boost pressure control solenoid valve actuation

    Boost pressure

    Solenoid valve for boost pressure control closed

    Engine speed

    If the boost pressure control solenoid valve is not actuated every 10 seconds "Display field 2" check the boost pressure control solenoid valve => page 23-50.

    Test boost pressure control solenoid valve > < Test boost pressure - engine code AGR