Intake Air System, Leak-Testing

Intake Air system, leak-testing

Checking with engine leak detector spray G 001 800 A1

Special tools, testers, measuring instruments and auxiliary items required

- VAG 1551/1552 Scan Tool with VAG 1551/3B adaptor cable
- G 001 800 A1 Engine leak detector spray

Test conditions
- Engine Coolant Temperature 85 °C minimum.

Test sequence

NOTE:

- The vacuum in the intake system will cause the leak detector spray to be drawn in with the unmeasured air. The leak detector spray reduces the ignitability of the mixture. This leads to a drop in engine speed and to a change of Oxygen sensor reading.
- Observe all safety precautions listed on the container.
- Connect VAG 1551/1552 Scan Tool, Refer to "Computers and Control Systems", [1][2][3]Reading and Clearing Diagnostic Trouble Codes
- Start engine and let idle
- Press 0 and 1 buttons to select "Address word" 01 "Engine electronics"

Display will appear as shown

Rapid data transfer HELP
Select function XX

- Press 0 and 8 buttons to select Function 08: "Read measuring value block"
- Press Q button to enter input

Display will appear as shown

Read measuring value block HELP
Input Display group number XXX

- Press 0, 0 and 1 buttons to select "Display group 1"
- Press Q button to enter input

Display will appear as shown (1 to 4 = Display zones)

Read measuring value block 1 ->
1 2 3 4

- Note Oxygen sensor control in Display zone 3 on chart.







- Systematically spray parts of air intake system with engine leak detector spray.

If engine speed drops or if value displayed for Oxygen sensor control changes:

- Press -> button.
- Press 0 and 6 buttons to select Function 06: "End data output"
- Press Q button to enter input
- Switch OFF ignition.
- Check sprayed areas of air intake system for leaks and correct as necessary.