Remove/install O2 sensor · ar0704s0080sd · Mercedes-Benz WIS

AR07.04-S-0080SD

Remove/install O2 sensor

8.4.10

ENGINES 646 in MODEL 636
with CODE (MF8) Low-emission engine conforming to EU3 group 3
with CODE (MF4) Low-emission engine conforming to EU4 group 3

ENGINES 646 in MODEL 639 with CODE (MF4) Low-emission engine conforming to EU4 group 3

N14.00-2026-06

1 Engine air intake duct

G3/2 O2 sensor, upstream of CAT

X35/56 O2 sensor connector

 	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
1	Remove engine intake air duct (1) at air filter	 To do this loosen clamp.
2	Remove connector for O2 sensor (X35/56) at bracket
3	Disconnect connector for O2 sensor (X35/56)
4	Remove O2 sensor upstream of catalytic converter (G3/2)	 Installation: Coat thread on O2 sensor upstream CAT (G3/2) with heat-resistant lubricant.
			*BA07.04-N-1001-01E
		 Box wrench bit	*000589710300
		Paste, hot lubrication 1 kg, DB supply specification 6879.20	*BR00.45-Z-1005-06A
5	Install in the reverse order
	Checking
 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
6	Check leaktightness of exhaust system when engine is running

 Sensors

Number	Designation		Engine 646 with code MF4 in model 639	Engine 646 with code MF4, MF8 in model 636


BA07.04-N-1001-01E	O2 sensor on catalytic converter	Nm	45	45

Box wrench bit

000 589 71 03 00

Repair materials

Number	Designation	Order number
BR00.45-Z-1005-06A	Paste, hot lubrication 1 kg, DB supply specification 6879.20	A 000 989 76 51

as0000z000201a Risk of injury. Skin or eye injuries may result when handling hot or glowing objects.
as0000z000501a Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.