Stile

Hello everyone!

Had to make a new topic, because I could not find any help to my problem from search.

So, new C63 owner here. I have owned the car nearly two weeks now and got some problems with CEL.

P2196 - 02 Sensor Signal Stuck Rich bank1 Sensor1. Read by OBD ELM327 + Torque App.

Replaced the sensor with new Bosch sensor, but got the CEL back on at the same day. The CEL comes normal about 1-2 miles after start. The car runs great and no other problems. Car is 2009 and 65k miles on the odometer. Previous owner said that the car has ECU tune, but was not sure who made it. He also bought it with tune on it.

-Stile

CarHopper

65,000 miles on the speedo?!?! Slow down sister! (odometer)

Cats are parts that can wear out and go bad too... I would either A) retune with an updated tune from a company with a good reputation or B) plan on replacing the cat if you want the CEL to go away.

bhamg

Do you still have secondary cats installed?

CarHopper

Why would that matter? Secondary cats have nothing to do with o2/cats etc. They are just there but make no difference especially when it comes to CELs

bhamg

"Stuck rich" means a failure of the of the voltage generated by the rich/lean test of the emissions system to reach the appropriate level, hence the "stuck" code. There's a wider voltage swing generated on the rich test vs the lean test.

bhamg

Sorry, bit of brain fade, am working on a project...what I meant to ask is how intact and original the whole exhaust system is back to the secondaries and particularly the rear o2 sensors.

CarHopper

^Yeah, no worries. Just making sure that things didn't go off course right away as the secondaries mean nothing really.

Stile

Thanks for the answers. The car has x-pipe installed by previous owner, but otherwise exhaust is stock. Yesterday when I looked the exhaust, I noticed a little leak on the x-pipe.

And yes odometer, no speedometer.

CarHopper

A leak on your x-pipe wont cause a CEL. Again, if you already replaced the sensors, there is either something going on with the tune or the cat itself.

bhamg

The reason I even posted on this thread was that in the past I troubleshot this very code for a friend's car, but his exhaust was modified throughout and tuned to account for those changes. So whereas I have usable, maybe even valuable insight into that particular case an essentially OE exhaust opens up more variables that I wouldn't presume to be able to address (I just googled the code to see what else was possible). Sorry and GL, I suspect the tune has something to do with it. One thing I would do is to monitor some real-time live data just to make sure the basics are addressed first.

Stile

Okey, thanks! What should I monitor?

bhamg

I have a handheld tool so I've never used the Torque app but you have it all in there - fuel system, catalyst, emissions systems, closed-loop operation, O2 sensors etc. Just make sure all returned sensor values are within normal ranges.