With Manufacturer's Scan Tool

Intake system, checking for leaks (unmetered air)

Checking with Engine Leak Detection Spray

Special tools and equipment

- V.A.G 1551 Scan Tool (or VAG 1552 mobile scan tool) with VAG 1551/3 cable
- Engine leak detection spray G 001 800 A1

Test condition

- Coolant temperature must be at least 80 °C, See Display group 04, display field 3

Test sequence

NOTE:
- The negative pressure in the intake system sucks in the leak detection spray with the unmetered air. Leak detection spray decreases ignition quality and performance of the fuel mixture. This causes a drop in engine speed and changes the value produced by the Heated Oxygen Sensor (HO2S).
- It is absolutely necessary to follow the safety precautions listed on the can.
- Connect V.A.G 1551 scan tool (VAG 1552). Start engine and select Engine Control Module (ECM) using address word 01. [1][2][3]Connecting VAG 1551 Scan Tool

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read measuring value block" function 08. Press -Q- button to confirm input.

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press 0, 0 and 1 for function "display group number 1", and then press Q to exit from input mode.

Indicated on display (1 - 4 = display fields)

Read Measuring Value Block 1 ->
1 2 3 4

- Observe engine speed in display field 1, and oxygen sensor control in display fields 3 and 4.

NOTE:
- Display field 3 = cylinder bank 1, on right when facing in direction of travel
- Display field 4 = cylinder bank 2, on left when facing in direction of travel
- Spray intake system parts with engine leak detection spray in a systematic manner.

If engine speed drops or if oxygen sensor control changes:
- Press -> button.
- Press buttons -0- and -6- to select "End data transfer" function 06. Press -Q- button to confirm input.
- Switch ignition off.
- Check sprayed part of intake system for leaks, and eliminate error.