O2 Sensor Replacement DIY with Pics.
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Joined: Jul 2012
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From: VA
98-E320 (retired)/97-E320/10-ML350
O2 Sensor Replacement DIY with Pics.
Recently received CEL on 1998 E320. Had Advance Auto Parts run the codes and got the following:
P0400 – EGR Flow
P0161 – O2 sensor heater circuit bank 2 sensor 2
P0156 – O2 sensor circuit bank 2 sensor 2
Called 2 different Mercedes-Benz Dealership and checked that Bank 2 Sensor 2 is Driver Side post CAT.
I decided to tackle this after researching here and Thanks to all for the information.
Here is the DIY with pictures.
1. Tools needed. (Jack Stand, Lift, 22mm Wrench, Pliers to lower lift, and Replacement Sensor)
2. Lift the car and place on Jack Stand using the rubber boot for tire change right under the plastic cover.
3. Unhook the old sensor from clips around the Transmission Pan. There are 2 and sensor cable might be black from years of dirt built up. (See Red marks in the picture below)
Sensor disconnected from wiring harness.
4. Using the 22 mm wrench loosen the old sensor (some elbow grease will be required)
5. After the sensor is loosened you can unscrew with hand.
6. The old one did its job.
7. Hand Screw the new sensor than use the 22mm wrench for the final stage to make it tight. (The new one I had came with some anti-seize paste on it already so don’t wipe it off.)Reconnect and re-clip to the transmission pan.
Good Luck.
I also did the EGV Valve cleaning and that was a hard but doable.
P0400 – EGR Flow
P0161 – O2 sensor heater circuit bank 2 sensor 2
P0156 – O2 sensor circuit bank 2 sensor 2
Called 2 different Mercedes-Benz Dealership and checked that Bank 2 Sensor 2 is Driver Side post CAT.
I decided to tackle this after researching here and Thanks to all for the information.
Here is the DIY with pictures.
1. Tools needed. (Jack Stand, Lift, 22mm Wrench, Pliers to lower lift, and Replacement Sensor)
2. Lift the car and place on Jack Stand using the rubber boot for tire change right under the plastic cover.
3. Unhook the old sensor from clips around the Transmission Pan. There are 2 and sensor cable might be black from years of dirt built up. (See Red marks in the picture below)
Sensor disconnected from wiring harness.
4. Using the 22 mm wrench loosen the old sensor (some elbow grease will be required)
5. After the sensor is loosened you can unscrew with hand.
6. The old one did its job.
7. Hand Screw the new sensor than use the 22mm wrench for the final stage to make it tight. (The new one I had came with some anti-seize paste on it already so don’t wipe it off.)Reconnect and re-clip to the transmission pan.
Good Luck.
I also did the EGV Valve cleaning and that was a hard but doable.
