Air Intake Unit Upper Cover

Air Intake Unit Upper Cover

• There are different versions of the air intake unit and corresponding upper cover ( up to 05.04 Version"1" and after 05.04 Version "2" as a running change, distinguishing characteristics => [ Characteristics of Air Intake Unit Versions 1 and 2 ] Characteristics of Air Intake Unit Versions 1 and 2). If the Version "1" upper cover or housing produced up to 05.04 has to be replaced, replace the cover or upper housing of the air intake unit as well (you will only receive Version "2" components as the spare part).

Removing

- Switch off ignition.

- Remove the plenum chamber cover.

CAUTION!
Even when the engine is cold, both pump/valve unit valves can be hot.

- Remove the windshield wiper arm and cowl panel trim.

- If necessary, remove the dome brace (not present in all vehicles).

- Remove the Air Quality Sensor (G238) if installed in this vehicle => [ Air Quality Sensor ] Service and Repair.

- Remove bolts - A -.





- Remove the upper cover - B -.

Installing

- Before installing the air intake unit upper cover, make sure connectors - C - through - F - and the grommet - B - are seated correctly and the cable - A - is routed correctly.





- In vehicles with a Version "1" air intake unit (running change to Version "2" beginning 05.04, distinguishing characteristics to Version "2"=> [ Characteristics of Air Intake Unit Versions 1 and 2 ] Characteristics of Air Intake Unit Versions 1 and 2) place a caulking strip (2 x 2 mm) in groove - D - of upper cover - A -, or seal the tongue and groove joint to the housing - B - e.g. with silicone sealant "D 176 001 A3".





- In vehicles with a Version "1" air intake unit, seal the area between upper cover - A - and housing - B - (or the inner cover) in area - C - e.g. with silicone sealant "D 176 001 A3".

- Reinstall the air intake unit upper cover - B -.





- Hand-tighten mounting bolts - A - (10 Nm).

- Install the removed components again in reverse order.

- Check the DTC memory for the Climatronic Control Module (J255) A/C control head and erase any faults displayed if necessary => Vehicle Diagnosis, Testing and Information System VAS 5051.

- If necessary, perform a basic setting and output diagnostic test mode on the A/C system.