srydy

Hi All,

I get CEL due to codes P0141 and P0136 (O2 sensor malfuncition).

What is the best course of action:
1) Should I take it to the shop right away?
2) Save some money and do it myself (I am a total newbee with some basic skills). Could some one please point me to DIY instructions for this repair.
2a)How many O2 sensors are there in the 2000 E55 and how many should I replace?

Thanks for your time,
srydy

Schweinhund

I believe there are four. If they have never been changed, you probably should change them. How many miles on your car?

srydy

The car has ~130K miles.

RobertG

It is easier to get to them from under the car, If I remember correctly I used a 7/8" wrench and replaced one sensor at a time so i dont mixup the connections.
After you have replaced the sensors and the light goes out I would clear the codes from memory.

srydy

Thanks RobertG. Are all 4 sensors the same (same part number)? The autohausaz site returns several parts, not sure which ones I would need.

RobertG

Look for upstream and down stream in the discription.

RobertG

I just look up and it says left or right front or rear. Use OEM

srydy

So, these are what I would should order(can you please confirm):
Bosch 13782 Oxygen Sensor, OE Type Fitment (Rear) -- 2
Bosch 13642 Oxygen Sensor, OE Type Fitment (Front Left) -- 1
Bosch 13798 Oxygen Sensor, OE Type Fitment (Front Right) -- 1

RobertG

srydy

Thanks RobertG. I could not find any DIY instructions for this repair (found something for E320 out in the web but not E55). Do you think you can point me to something?

RobertG

Code 136 is lean exhaust and 141 is bank 1 sensor 2.
sensor 2 would mean downstream or rear.
With the # of miles on the clock replace all of them it's a bit pricy but you'll have a peace of mind.

RobertG

The location of the o2 sensors are same on e-55 and e-320.
take care when disconnecting the connectors(press a tab ) and it will come appart, it is keyed so it goes only one way. Tighten it like you would tighten a spark plug.

RobertG

https://mbworld.org/forums/c-class-w...placement.html

-fad

All advice is spot on.

Experienced same codes & replaced oxygen sensors in my '01 E55- super easy w/ a crows foot, oxygen sensor socket, and 1/2" socket wrench & extensions.

You may wish to consider replacing just the failed parts. Can't really predict the life left in fronts- some Original Equipment Bosch Oxygen Sensors easily last 150k miles.

The different parts numbers correspond to the length of the attached wires. The rears have the longest length.

The DYI is spot on. Total time should be no longer than 30 mins for both rears, once you complete the first rear, the second rear will be a 5min piece of cake.

Hope this helps,