Remove/install heated O2 sensor

AR07.52-P-5303CW

Remove/install heated O2 sensor

16.5.11

 

Remove/install

 Danger!

Risk of injury to skin and eyes caused by handling hot or glowing objects.

Wear safety gloves, protective clothing and safety glasses, if necessary.

AS00.00-Z-0002-01A

 Danger!

Risk of death caused by vehicle slipping or toppling off of the lifting platform.

Align vehicle between columns of vehicle lift and position four support plates at vehicle lift support points specified by vehicle manufacturer.

AS00.00-Z-0010-01A

1

Raise vehicle

2

Remove rear section of the lower engine compartment paneling

Model 204

Model 172

AR61.20-P-1105W

Model 207, 212

AR61.20-P-1105EW

 Installation: Install engine compartment paneling only after engine test run.

Oxygen sensor downstream of catalytic converter (G3/1)

3

Unclip and disconnect electrical connection for oxygen sensor downstream of CAT (G3/1x1) on bracket

 Unclip electrical line for sensor from bracket (1).

4

Remove oxygen sensor downstream of CAT (G3/1) from CAT (4)

 Installation: Coat thread with paste.



*BA14.00-P-1001-01A

Paste

*BR00.45-Z-1005-06A

Oxygen sensor upstream of catalytic converter (G3/2)

5

Unclip and disconnect electrical connection for oxygen sensor upstream of CAT (G3/2x1) on bracket

 Engine 271.9: Unclip electrical line from bracket (2).

6

Unclip electrical line for oxygen sensor upstream of CAT (G3/2) on heat shield for the right engine mount

7

Remove oxygen sensor upstream of CAT (G3/2) from CAT (4)

 The oxygen sensor upstream of CAT (G3/2) is a wideband sensor and therefore is extremely sensitive to the effect of applied forces. Pay attention to the following points otherwise the oxygen sensor upstream of CAT (G3/2) will be damaged:

 Engine 271.9: Do not pull out oxygen sensor upstream of CAT (G3/2) using pliers: just place with an open end wrench on the hexagon.

 When cleaning the thread, do not use any force (e. g. with pliers or vise) on the stem of the oxygen sensor upstream of CAT (G3/2).

 Engine 271.9: When replacing the oxygen sensor upstream of CAT (G3/2) the balance resistor (3) for the new oxygen sensor (G3/2) is already put on and must not be replaced (resistance depends on the sensor).

 Installation: Coat thread with paste.



*BA14.00-P-1001-01A

 Engine 271.8

*000589710300

Paste

*BR00.45-Z-1005-06A

8

Install in the reverse order

9

Attach STAR DIAGNOSIS and perform default initialization of the ME-SFI [ME] control unit

After replacing the oxygen sensor upstream of CAT (G3/2)

 A default initialization must be conducted using STAR DIAGNOSIS in the ME-SFI [ME] control unit under the menu item "Control unit adaptations" since the mixture adaptation of the ME-SFI [ME] control unit must be reset.

 Danger!

Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running

Secure vehicle to prevent it from moving by itself.
Wear closed and snug-fitting work clothes.
Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

10

Perform engine test run while checking the exhaust system for leaks

Number

Designation

Engine
271

BA14.00-P-1001-01A

O2 sensor on exhaust pipe/ exhaust manifold

Nm

50

Number

Designation

Order number

BR00.45-Z-1005-06A

Paste, hot lubrication 1 kg, DB supply specification 6879.20

A 000 989 76 51