Stuck in SMOG limbo with oxy sensors not ready. Replaced them, no joy.
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Joined: Mar 2013
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C63 AMG
Stuck in SMOG limbo with oxy sensors not ready. Replaced them, no joy.
Looking for some experienced opinions. Couldn't pass smog due to oxygen sensor and oxygen sensor heater not ready. Was told to keep driving but months of driving never reset them. Finally went to dealer and they couldn't reset them telling me one of them "was not getting up to a level it was supposed to". They did the Merc standard reset drive. Dealer said replace all 4 and 90% chance it will fix it, $2,150 for the job.
At that point I declined the rape kit and took my car home, plugged in the iCarsoft and started monitoring oxygen sensor voltages. My upstream pair show "ja" for active, which I think means yes, and the downstream pair always say "NO". I have no option to view upstream voltage but the downstream voltage jumps around quite a bit and the left and right don't really track each other. I then replaced all 4 myself and everything looks exactly the same. There have never been any codes or CEL except for one unrelated code that is undefined and listed all over there place as ignorable. I have not disconnected the battery or reset the ECU.
I've since driven a couple hours over 5 trips and the downstream sensors continue to show "NO" under operational and the oxygen sensor and heater still show not ready. Car is at 105k, is the bouncing downstream voltage indicitive of bad cats? Should the downstream voltage remain steady on a W204 AMG after warmup?
Please hit me with opinions and troubleshooting ideas.
Thanks!
At that point I declined the rape kit and took my car home, plugged in the iCarsoft and started monitoring oxygen sensor voltages. My upstream pair show "ja" for active, which I think means yes, and the downstream pair always say "NO". I have no option to view upstream voltage but the downstream voltage jumps around quite a bit and the left and right don't really track each other. I then replaced all 4 myself and everything looks exactly the same. There have never been any codes or CEL except for one unrelated code that is undefined and listed all over there place as ignorable. I have not disconnected the battery or reset the ECU.
I've since driven a couple hours over 5 trips and the downstream sensors continue to show "NO" under operational and the oxygen sensor and heater still show not ready. Car is at 105k, is the bouncing downstream voltage indicitive of bad cats? Should the downstream voltage remain steady on a W204 AMG after warmup?
Please hit me with opinions and troubleshooting ideas.
Thanks!
Last edited by MBAdon; Nov 27, 2019 at 12:45 PM.
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12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
It really sounds like you have a tune and post cat o2’s are turned off because if they are tuned on they will either go ready or set a check engine light and efficiency codes eventually but eventually is like a week of normal driving max. Did you tune the car or possibly buy it with a tune unknown to you and this is your first emissions check? Tunes that tune off the 02’s turn off the o2 heaters also so suspicious of a tune. The o2’s will look normal on a monitor as they still send the signal but the Ecu ignores the reading if the channel is disabled.
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2010 C300 4MATIC........ 2011 C63 AMG.............. 2015 CLS400 4MATIC.....
Yea are you tuned?
Otherwise the secondary air system puts air into the cats, but you would probably have a CEL if that didn't work
Otherwise the secondary air system puts air into the cats, but you would probably have a CEL if that didn't work
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2007 Mercedes E63 AMG
not ready of which never changes means you have a tune that has coded them out. if paired with not ready for heater circuit, means for sure you have a tune that has coded them out.
its a shame that many of you newer members are purchasing cars that have tunes but no programmer to revert. the shops/tuners who are selling these are making double off of all of you by reselling you what you already have. a tune but the ability to revert to stock.
its a shame that many of you newer members are purchasing cars that have tunes but no programmer to revert. the shops/tuners who are selling these are making double off of all of you by reselling you what you already have. a tune but the ability to revert to stock.
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C63 AMG
Crap guys, yes I totally have a tune. I guess I forgot about that since I've had it since 2012 and I don't remember having a problem before. Eurocharged v4, and I have the programmer and everything. I will take that off and report back after driving a bit. I have had several SMOGs since 2012 and passed with the tune, although I remember once when it was v3 I had to take it off so RPM could be held at a certain RPM that the tune didn't allow.
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Joined: Mar 2013
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C63 AMG
Edit: looks like smog is every two years here so it must have been 2017.
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12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
I still think it is the tune or you would get a light but not sure how you passed 2 years ago. I would flash back to stock file and drive it around and see if you get readiness, I can usually flash back to stock and do a 40 minutes loop and get readiness. I try to do this drive cycle roughly seems to work to get readiness as fast as possible https://www.instructables.com/id/How...or-Smog-Check/
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C63 AMG
Well I flashed it back to stock and took a drive and sure enough both of the downstream sensors are now saying "ja" for operational. Running the smog scan now shows the oxygen sensor heater ready, the oxygen sensor not ready and now the catalytic is showing not ready, but its a change! I am betting I just need to do the drives and it will reset. Will post back after driving more.
Thanks!
Thanks!
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'16 CLS63S
Not reading the whole thread but have you tried to ask Eurocharged for a smog tune? They may or may not give it to you. It will set all the monitors ready regardless of whats wrong with the car and wont pop a CEL. Of course this doesn't actually solve any real CEL issues you may be having but at least you'll pass smog
