Intake Air System, Checking For Leaks (False/Unmetered Air)

Checking For Leaks In The Intake Air System

Checking with engine leak detector spray G 001 800 A1

NOTE:
- The vacuum in the intake system will cause the leak detector spray to be drawn in with the unmetered air. The leak detector spray reduces the flamability of the mixture. This leads to a drop in engine speed and to a change of oxygen sensor reading.
- The safety precautions listed on the container must be adhered to.

Special tools and equipment
- V.A.G1551 Scan Tool (ST) or VAG1552 mobile scan tool with VAG1551/3 adapter cable
- Engine leak detector spray G 001 800 A1

Test conditions
- Coolant temperature at least 85°C.

Test sequence
- Connect VAG1551 (VAG1552) Scan Tool (ST).
- Turn on ignition and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (when doing this engine must be running at idle).

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08 and press -Q- button to confirm input.

Indicated on display

Read Measuring Value Block
Input display group number XXX

- Press buttons -0-, -0- and -1- to input display group number 1 (001) and press -Q- button to confirm input.

Indicated on display: (1-4 = display fields)

Read Measuring Value Block 1 ->
1 2 3 4

- Check whether coolant temperature is above 85°C in display field 2.
- Observe engine speed in display field 1 and the oxygen sensor control before Three Way Catalytic Converter (TWC) in display field 3.

Display Group 1:

- Systematically spray components of the intake system with engine leak detector spray.

If the engine speed drops or the oxygen sensor control changes:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06 and press -Q- button to confirm input.
- Turn off ignition.
- Check sprayed areas of intake system for leaks and correct if necessary.

If the engine speed and the oxygen sensor control do not change:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06 and press -Q- button to confirm input.
- Turn off ignition .