CEL for rear O2 sensor
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'02 C230K
CEL for rear O2 sensor
I had a parts store pull the code for me. Some posts suggest that this may be triggered by a bad MAF. Before I go to the dealer I'd like to know a couple of things: Is the O2 sensor part of an emmissions warranty (75k on car)?
MAF was replaced once already before 50K-Is part warranted?
Is the code a hard set or would it clear after a few cycles?
Any additional feedback would be appreciated.
MAF was replaced once already before 50K-Is part warranted?
Is the code a hard set or would it clear after a few cycles?
Any additional feedback would be appreciated.
#3
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Much of that is covered under the emmissions warranty so I would start there. You didn't say what codes you got and if you don't have a scan tool to check codes and sensor output and understand what's normal you'll just be spending lots of money chasing maybes. Think about it, just parts costs for a MAF is $350, O2 sensor $180 each (2 of them), then what else will you replace?
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Hey Buell ! How the hell are you? Thanks for pitching in again. I'll try to get more facts. Check the CLK forum for my only post there, I value your opinion.
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2011 C 300 4-Matic
The MAF will not trigger rear 02 sensor codes. Most likely its a faulty 02 sensor. The rear 02 sensor only monitors if the catalytic converter is working properly. If the cat isnt doing its job, it will set a cat inefficiency code. If the code just says problem with the rear 02 sensor, its probably just that.
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'02 C230K
Just to wrap this up. I found an independent shop with the MB computer. They replaced the rear O2 sensor that set the code. I had the front replaced as well, based on their reccomendation. Thanks for all your input.
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#8
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The MAF will not trigger rear 02 sensor codes. Most likely its a faulty 02 sensor. The rear 02 sensor only monitors if the catalytic converter is working properly. If the cat isnt doing its job, it will set a cat inefficiency code. If the code just says problem with the rear 02 sensor, its probably just that.
But what exactly is the problem when both pop up?
O2 or Cat's?
Last edited by vsix; 11-01-2015 at 02:27 PM.