Remove/install heated O2 sensor - AR07.52-P-5303MR

ENGINE 274 in MODEL 172, 204, 207

Shown on model 204

Fig 1: Identifying Heated O2 Sensor Remove/Install Components - Shown On Model 204

Courtesy of MERCEDES-BENZ USA

	Risk of injury . Skin or eye injuries may result when handling hot or glowing objects.	Wear protective gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
	Remove/install
1	Remove upper engine cover
2	Disconnect electrical connection (G3/2x1)	Unclip electrical line from holder.
3	Remove oxygen sensor (G3/2) from catalytic converter	Coat thread with heat-resistant lubricant. Ensure that line for oxygen sensor is routed correctly.
		Oxygen sensor upstream of catalytic converter	*BA14.00-P-1005-01A
		Paste, hot lubrication 1 kg, DBL 6879.20	*BR00.45-Z-1005-06A
		Engine mount wrench set	Figure
4	Lift vehicle on vehicle lift	Engine 274 in model 172, 204.0/2/3, 207
5	Remove lower engine compartment paneling	Engine 274 in model 172	AR61.20-P-1105W
5	Remove lower engine compartment paneling	Engine 274 in model 204.0/2/3, 207	AR61.20-P-1105EW
6	Disconnect electrical connection (G3/1x1)	Unclip electrical line from holder.
7	Remove oxygen sensor (G3/1) from catalytic converter	Coat thread with heat-resistant lubricant. Ensure that line for oxygen sensor is routed correctly.
		Oxygen sensor at catalytic converter	*BA14.00-P-1002-01A
		Paste, hot lubrication 1 kg, DBL 6879.20	*BR00.45-Z-1005-06A
		Engine mount wrench set	Figure
8	Install in the reverse order
9	Read out fault memory using the diagnostic system and clear if necessary
			AD00.00-P-2000-04A
	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.	Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
10	Carry out an engine test run and check exhaust system for leaktightness

OXYGEN SENSOR

Number	Designation		Engine 274
BA14.00-P-1002-01A	Oxygen sensor at catalytic converter	Nm	50

OXYGEN SENSOR

Number	Designation		Engine 274
BA14.00-P-1005-01A	Oxygen sensor upstream of catalytic converter	Nm	50

Fig 2: Identifying Engine Mount Wrench Set (001 589 01 16 00)

Courtesy of MERCEDES-BENZ USA

REPAIR MATERIALS

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