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Manifold Pressure/Vacuum Sensor: Testing and Inspection

CHECKING INTAKE MANIFOLD ABSOLUTE PRESSURE SENSOR

Procedure

- Connect VAG 1551 Scan Tool (ST).
- Start engine and let idle.
- select function 08 "Read measurement block".

^ Display will appear as shown:

Read measurement block 1
1 2 3 4

NOTE: Only continue testing if the coolant temperature is over 85°C (185°F).

- Read display value in channel 4.
- Display must be 20 - 40 % and fluctuating.
- If a constant value of approximately 90 % is displayed:

- Check vacuum hose to Digifant Engine Control Module (ECM) (J169).
- If necessary replace ECM.
- Press --> button.
- Press 0 and 6 buttons to select function 06 "end data transfer".
- Press Q button to enter input.