Oxygen Sensors
Thread Starter
Member
Joined: May 2008
Posts: 148
Likes: 1
From: Calgary Alberta Canada
03 Silver E55
Oxygen Sensors
I am in need of some new oxygen sensors and was wondering if someone could point me in the best direction.
I just replaced them 2 months back (if even that), however due to my car running so pig rich I believe they are dead again. When I plug my scanner in and get on the gas all the sensor voltages drops to 0 and my car throws a CEL for "O2 sensor activity" one for each.
I just replaced them 2 months back (if even that), however due to my car running so pig rich I believe they are dead again. When I plug my scanner in and get on the gas all the sensor voltages drops to 0 and my car throws a CEL for "O2 sensor activity" one for each.
Super Member
Joined: Feb 2010
Posts: 554
Likes: 0
From: Mississippi
2004 SL55
In the same boat as you. My car has been running pig rich since I put my headers on (even with a tune). I think it is bc my O2 sensors were extended incorrectly, causing CEL codes, which in turn is making it run rich again. You might find the part number you need from AutoZone (or a similar store) and then shop around on eBay or Amazon for them to save a few $$$. My car is currently parked in the garage. I had to take the O2 sensors off and mail them to someone that could properly extend them and make sure the wiring was done correctly.
Sorry this doesn't directly answer your question
Sorry this doesn't directly answer your question
MBWorld Fanatic!
Joined: Mar 2010
Posts: 1,909
Likes: 4
From: San Diego
F-250
Who extended your O2 sensor? I really don't like this about the long tubes, on the other hand, it is fixable.
I have heard that if you extend the wiring, you do it on the car sidfe, before the connector. If you extend the connector wiring, most run into trouble.
I have heard that if you extend the wiring, you do it on the car sidfe, before the connector. If you extend the connector wiring, most run into trouble.
Super Member
Joined: Oct 2009
Posts: 661
Likes: 3
From: Saudi Arabia - Qatif
Brabus K8 E55 05
Well, I suspect mine are not functioning properly too but I have all cats deleted. Well, How many O2 sensors are available? 4?
I was searching on the net and I found some with connection ready to replace old with. I am not sure if they will need cut and extend, I run Kleemann headers and not Long Tube headers.
http://www.buyautoparts.com/autopart...en_Sensor.html
I was searching on the net and I found some with connection ready to replace old with. I am not sure if they will need cut and extend, I run Kleemann headers and not Long Tube headers.
http://www.buyautoparts.com/autopart...en_Sensor.html
MBWorld Fanatic!
Joined: Mar 2010
Posts: 1,909
Likes: 4
From: San Diego
F-250
02 sensor extension?
I hope some guys post up what options they have used here for extending O2 sensors. A lot of new headers going on through the group buys, and nothing worse than a new part that causes problems.
I will tell you this: There is no discounting the ability to datalog. I can see exactly what my AFR's are running under real world conditions as well as on the dyno.
Having Long Term and Short term fuel trims is equally important. This about this:
People are putting on headers, and begin running rich. Theoretically, the adds airflow should create a lean condition. Well you would be right. What you will see with the headers is that the LTFT is adding fuel to compensate for the added air. This will dump lots of fuel as a failsafe to the lean condition. I had this when I first installed my headers. A good tune will bring you back to normal, and then you will run on the maps as designed.
I will tell you this: There is no discounting the ability to datalog. I can see exactly what my AFR's are running under real world conditions as well as on the dyno.
Having Long Term and Short term fuel trims is equally important. This about this:
People are putting on headers, and begin running rich. Theoretically, the adds airflow should create a lean condition. Well you would be right. What you will see with the headers is that the LTFT is adding fuel to compensate for the added air. This will dump lots of fuel as a failsafe to the lean condition. I had this when I first installed my headers. A good tune will bring you back to normal, and then you will run on the maps as designed.
MBWorld Fanatic!
Joined: Jan 2004
Posts: 7,092
Likes: 13
From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
+1 with above and also I have been running extended o2 sensor wires for years and years without a hitch.
Don't let anyone tell you it can't be done. If we were running F1 cars yes the degradation of signal would be something that should be taken into account.....they're 4 door luxury liners. It's fine!
I am running the Universal Bosch extenders and it runs great. I was having trouble with my O2s due to MY error of crossing wires and got the same as the first post until I fixed the short circuit. Now all is well.
Same thing too bro, when I gave mine gas she went right to zero and then eventually would throw CEL. It was 2 wires crossed.
Here is the Bosch unit. Not pic of my car. Just off net.
Don't let anyone tell you it can't be done. If we were running F1 cars yes the degradation of signal would be something that should be taken into account.....they're 4 door luxury liners. It's fine!
I am running the Universal Bosch extenders and it runs great. I was having trouble with my O2s due to MY error of crossing wires and got the same as the first post until I fixed the short circuit. Now all is well.
Same thing too bro, when I gave mine gas she went right to zero and then eventually would throw CEL. It was 2 wires crossed.
Here is the Bosch unit. Not pic of my car. Just off net.
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MBWorld Fanatic!
Joined: Mar 2010
Posts: 1,909
Likes: 4
From: San Diego
F-250
^ I was told they dont make an extender. Actually, I was told they dont make a round extender (Yours is square). I need to look at an O2 at home.
My extra O2s for logging are no issue. I have extra slack.
Part number? Thanks Jakpro
My extra O2s for logging are no issue. I have extra slack.
Part number? Thanks Jakpro
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Thread Starter
Member
Joined: May 2008
Posts: 148
Likes: 1
From: Calgary Alberta Canada
03 Silver E55
The only 2 wires I could imagine being crossed are the two whites. I was running fine for a while and then I took her to the track and a day later I was getting CELs again.
I am running the universal Bosch ones that came with extremely long harness, so my only splice was to add the connector.
I am running the universal Bosch ones that came with extremely long harness, so my only splice was to add the connector.
Super Member
Joined: Feb 2010
Posts: 554
Likes: 0
From: Mississippi
2004 SL55
The only 2 wires I could imagine being crossed are the two whites. I was running fine for a while and then I took her to the track and a day later I was getting CELs again.
I am running the universal Bosch ones that came with extremely long harness, so my only splice was to add the connector.
I am running the universal Bosch ones that came with extremely long harness, so my only splice was to add the connector.
"On most cars the two white wires are interchangeable, but MB electronics are so sensitive that it will cause a code if not wired correctly. This is why I suggest wiring it on the harness side, as every wire is a different color, vs the sensor side having two white wires. Plus it makes swapping sensors out much easier. Unfortunately MB has no diagrams on the sensor itself."
Hope this helps.
