Anybody have experience in O2 sensor reading
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From: Chicago
E63 SL55 996TT C5Z06
I would be interested in understanding this as well as I may have this camshaft sensor leaking oil issue, expand to my O2 sensor connectors
my Icaraoft diagnostic tool will read the O2 sensors but I don’t no exactly what I’m looking for with the data
my Icaraoft diagnostic tool will read the O2 sensors but I don’t no exactly what I’m looking for with the data
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Cls63 s-amg 2014
I have same your problem
Super Member
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From: PA
2019 E63s AMG
A year or so ago I troubleshot an issue with one of my O2 sensors. The most notable thing about my troubleshooting was that the failed sensor had big voltage spikes as seen on your left O2 sensor. It should be more steady waves like the voltage on the right sensor. After replacing my faulty sensor, both looked almost identical on the live graph.
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09E350, 07E63, 13CLS63
I have read the causes of the O2 sensor error could be either the sensor is damaged or issue with the fuel injectors. Since i just replaced the 2 downstream sensors last year, its not likely that they went bad. The only thing left is the fuel injectors. Is it a big job? Have not found a video for M157. FCP has one for M156.
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W212 MY'14 M276-3.5NA @75kMi
I have read the causes of the O2 sensor error could be either the sensor is damaged or issue with the fuel injectors.
Since i just replaced the 2 downstream sensors last year, its not likely that they went bad.
The only thing left is the fuel injectors.
Is it a big job?
Have not found a video for M157. FCP has one for M156.
Since i just replaced the 2 downstream sensors last year, its not likely that they went bad.
The only thing left is the fuel injectors.
Is it a big job?
Have not found a video for M157. FCP has one for M156.
What are your upstream lambdas reporting ??
Downstream O2 flag cats efficiency.
Last edited by CaliBenzDriver; Jul 22, 2025 at 04:21 PM.
Super Member
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From: USA
09E350, 07E63, 13CLS63
I thought i posted the above on the other thread 😄.
Anyways, i dont have any error code other than P014A i have Foxwell scaner. How can I read the upstream lambdas? Thank you.
Anyways, i dont have any error code other than P014A i have Foxwell scaner. How can I read the upstream lambdas? Thank you.
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Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Lambdas are directly attached to ECU Module.
ECU Fuel trims may be listed under the OBDII menus.
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
EXHAUST LAMBDA SENSORS
Upstream exhaust Lambda sensors get contaminated by engine burning thin oil during combustion
and by external contamination through burned up CPS "oil-in-harness" traveling down into sensors.
So new Bosch sensors may bring temporary relief. Replacement restores lost engine performance.
and by external contamination through burned up CPS "oil-in-harness" traveling down into sensors.
So new Bosch sensors may bring temporary relief. Replacement restores lost engine performance.
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Replace sensors in pairs, both banks at the same time. Engine needs to be given a chance to be balanced, the opposite of unbalanced.
Start with 2x upstream Lambdas only and check all connectors including downstream O2 while under the car.
Last edited by CaliBenzDriver; Aug 11, 2025 at 06:39 PM.
