Intake Air System, Checking For Leaks (Unmetered Air)

Intake System, Checking For Leaks (Unmetered Air)

Checking with Engine Leak Detection Spray G00 1 800 A1

Special tools and equipment
- V.A.G 1551 scan tool (or VAG 1552 mobile scan tool) with VAG 1551/3B cable
- Engine leak detection spray G 001 800 A1

Test requirement
- 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 the Engine Control Module (ECM) using address word 01. (connecting scan tool and selecting ECM). Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG 1551 Scan Tool", Testing and Inspection

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
Enter display group number XXX


- Press buttons -0-, -0- and -1- to select "Display group number 1". Press -Q- button to confirm input.

Indicated on display: (1 to 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 field 3.
- 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 the error.