Intake Air System, Checking For Leaks (False/Unmetered Air)
Intake System, Checking For Leaks (Unmetered Air)
Checking with Engine Leak Detection Spray G 001 800 A1
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.
Special tools and equipment
- VAG1551 scan tool (or VAG1552 mobile scan tool) with VAG1551/3B cable
- Engine leak detection spray G 001 800 A1
Test sequence
- Connect VAG1551 scan tool (VAG1552). Start engine and select the Engine Control Module (ECM) using address word 01.
Connecting scan tool and selecting ECM. [1][2][3][4][5]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
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
- Check display field 2 to see whether the coolant temperature is above 85 °C.
- Observe engine speed in display field 1, and oxygen sensor control before catalytic converter in display field 3.
Display Group 1:
- Spray intake system parts with engine leak detection spray in a systematic manner.
If engine speed drops or if oxygen sensor control changes:
- Press the -> button.
- Press buttons -0- and -6- to select "End Output" function 06. Press -Q- button to confirm input.
- Switch ignition off.
- Check sprayed part of intake system for leaks, and eliminate the error.
If engine speed or oxygen sensor control does not change:
- Press the -> button.
- Press buttons -0- and -6- to select "End Output" function 06. Press -Q- button to confirm input.
- Switch ignition off.