Audi Workshop Service and Repair Manuals > A4 Mk1 > Power unit | Motronic injection and ignition system (6 cyl. turbo) | Mixture preparation system, electronic inj.,Gas | Servicing Motronic injection system | Checking intake air system for leaks (unmetered air)

Motronic injection and ignition system (6 cyl. turbo)

Servicing Motronic injection system

Checking intake air system for leaks (unmetered air)

Checking with engine leak detector spray G 001 800 A1

Notes:

◆ 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 ignitability of the mixture. This leads to a drop in engine speed and to a significant increase of the CO content.
◆ The safety precautions listed on the container must be adhered to.

‒ Connect up vehicle diagnostic, testing and information system VAS 5051 or fault reader V.A.G 1551 and select engine electronics control unit with "Address word" 01 .
For this purpose, the engine must be running at idle speed

→ Display:

Rapid data transfer HELP

Select function XX

‒ Press keys 0 and 8 for the function "Read measured value block" and confirm entry with Q key.

→ Display:

Reading measured value block

Enter display group number XXX

‒ Press keys 0, 0 and 1 for "Display group number 01" and confirm entry by pressing Q.

→ Display:
(1...4 = display zones)

Read measured value block 1 ⇒

1 2 3 4

‒ Note engine speed in display zone 1.
‒ Systematically spray parts of the intake system with engine leak detector spray.

If engine speed does not change:

‒ Press the ⇒key.
‒ Press keys 0 and 6 for the "End output" function and press the Q key to confirm entry.

If engine speed drops:

‒ Press the ⇒key.
‒ Press keys 0 and 6 for the "End output" function and press the Q key to confirm entry.
‒ Check sprayed areas of intake system for leaks and rectify if necessary.

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