Exotic-metal55

My data reader claims P0296 to be post cat to lean. I have cats but also have off road pipe set up. My rear 02`s are turned off and with off road pipes there is no code. With cats the code is constant and on both banks. My part throttle tune is on the rich side, as with my WOT. The code is a part throttle reading , as it comes on during normal driving. Time for inspection, so need to get all the codes clear and let parameters lock in.

Anyone have the same codes ?

skratch77

These cars are picky,why not just run with the rear 02s off but with the cats inplace?that wont throw any codes right?Or when you have the rears 02s off the car wont pass smog is what you mean?

chawkins2001

I had the exact code but was on a stock tune with some exhaust work. It was my o2 sensors that needed to be replaced, and it went away after the install.

Exotic-metal55

My rear 02 sensors are turned off and I will have to turn them back on to pass smog. It is a strange code, as I know the 02`s are off. I was getting this code, so I also changed my primary 02 sensors this week and code keeps coming back. STAR showed that I had weak voltage in the primary anyway. Those bosch 02`s only had 4K on them but rich race tune seemed to foul them out . I put Walker 02`s in this time.

Evolved8

I keep having this code pop up after my Eurocharged tune. I had the Lts installed on the old tune for over a month without a CEL... ?? p2096

chiromikey

i didn't think you could actually turn the o2 sensors "off"...just widen their threshold. it sounds like your tune has the post o2 sensor set to read with no cats and when you put cats back in those sensors obviously get a reading much leaner. why not just ask your tuner to modify the sensors to read with the cats then return to your current tune when you remove the cats after your smog inspection?

shardul

iTrader: (1)

good point!

skratch77

I have my rear 02s working like normal and sent my ecu to kleemann to go into the egr eeprom and switched the rear o2s to not monitor them.

Its not in the reg ecu eeprom where the tune is.you can try kleemann and see if it works.

I have no cats and the rear o2s are working and the car passes all readiness checks for inspection.

Nothing is scaled in the tune and the voltages are working like they should.They can take care of your problem without changing your ecu tune.

I think its like 150 to get it done.

shardul

iTrader: (1)

Yes the way kleemann does it they dont alter the ECU file.

Tibi

I am gettin p2096 and p2098 post catalyst fuel trim too lean bank 1 and bank 2. I have a eurocharged tune.

I spoke to Jerry and he said when you extend the 02s they become finicky and that he will need to retune my car and add more fuel. Still waiting...........not driving the car though since I don't want to have any issues.

Funny thing, after 80mm tb, longtubes and meth. When I was driving the car on stock tune it felt stronger than it did after my tune. And the only cel it threw was for the rear 02 no activity.

Just saying.

chiromikey

i definitely don't buy that extended o2's are causing all these different cel's, it just doesn't add up and there hasn't been a shread of proof to back it. i ran extended o2's in my long tubes with a kleemann tune for 3+ years without a single problem. immediately after removing my cats and trying a different tuner, i got my cel's...even after replacing several sets of new sensors per that tuners insistence.

Roverron

I had this problem for several months with SDS it showed a delayed reading of the problem O2 sensor. After reading in the SDS sim mode its says if both O2 sensors are having issues it's usually the primary sensor causing the fault beacuse the secondary O2 is reading the primary to figure out where it should be. Try running SDS and looking at actual values of lamba control. I'm sure you will see a lazy O2 sensor. I hope that make since. I will try and look up document and post.

TTMotorsports

I guess you really were listening when we were trying to figure out your issues Ron!

Brooke-
What does the voltage look like at all 4 O2 sensors? Is the voltage stagnant on any of them or showing signs of being lazy(lack of quick voltage change)?
I would just have Jerry "turn on" the rear O2's and see if that works.

Exotic-metal55

All well said. I do not run 02 extensions on my ride and still have the codes.

Bruce, that is my plan to have him turn the 02`s back on but he is in Washington this week, . Just trying to get a clean inspection, before putting my ported heads on.

saltydizzle

+1 I had this code pop up for me too, seems i had a voltage drop from the relay that controls the O2 sensor heating and aging function. replaced and seems to be good now.

TTMotorsports

Patience is a virtue my friend!

I am psyched you are getting your ported heads on your beast! FTMFW!!

SmokinCRC6

Brooke, In your Engine Diagnostics have your tuner change your DTCs table like this:



You won't get any error reporting and should have him change it back after inspection. You will pass whether you have cats or no cats.

cutt

is this the code for rear o2s, or front?

SmokinCRC6

I have found that disabeling just the rear 02s won't ready the ECM as complete. Easier to just disable all reporting and go get you sticker then change back.

Exotic-metal55

Larry , thanks but it seems the Benz tuenrs dont have tables like that to work with. At least I have not heard of them . One local guy sent his off to have the 02`s set to ready on his car and his ECU locked up. He is screwed now.

Bruce, yes I am putting ported heads on soon. They have been completed but then asked to have cam valley ground out more. Just in case I end up wanting a much larger cam than we have available these days.


Here are the idle readings on all four of my 02`s B1 S1 .795-.810mv B2 S1 .790-.810 mv Rear 02s B1 S2 and B2 S2 .065-.100MV average (might flash .710 for a moment but low voltage was the average.

cutt

i had to disconnect my battery two weeks ago, the light has not been back on yet

vioilio

Any update on the fix?
I'm experiencing P2096 (hard) and P0106 (pending). I have Long tube headers with primary and secondary cats deleted and TTM rear O2 extenders. Since the install and tune (1000 miles ago) the car was running great with no codes whatsoever until now. I just got those codes yesterday. Could it be the cold weather?
P.S. My rear O2's are NOT turned off.