Topic: CEL P2096 (Read 1639 times)

zeedeveel55 · « **on:** March 19, 2011, 08:02:46 PM »

Got a CEL when i turned my car on the other day going home from work.

P2096 - post catalyst fuel trim system too lean Bank 1

I couldn't really find too much definitive information on this on NASIOC. Any thoughts? Should I just replace the back o2 sensor? Do i need to call Dom and get this eliminated?

I just cleared it, Im thinking it will be coming back on.

gebby1029 · « **Reply #1 on:** March 19, 2011, 10:53:40 PM »

I just searched nasioc really quick and got 2 ideas; rear O2 sensor mounted in a spark plug anti-fouler, exhaust leak, log and have looked at.

I would send a log to Dom and get his opinion. Anyone with a laptop and tactrix cable should be able to do that for you. If it is nothing, the same two things can turn off that CEL code permanently.

TheBigChill · « **Reply #2 on:** March 20, 2011, 02:10:06 AM »

The rear O2 sensor on your car is used to make additional small changes to closed loop fueling, whereas in my car it's only used to monitor cat function. I'm willing to bet that your closed loop fueling is a touch rich now with this code. Maybe AFR's in the mid 13's rather than stoich. Don't just block the code, fix it. The whole process of simply eliminating the ECU's ability to throw certain codes is a haphazard way of doing things, IMO. Far from a fix. Log some closed loop operation, and send the logs Doms way, as Kevin suggested.

zeedeveel55 · « **Reply #3 on:** March 20, 2011, 09:51:37 AM »

Quote from: TheBigChill on March 20, 2011, 02:10:06 AM

The rear O2 sensor on your car is used to make additional small changes to closed loop fueling, whereas in my car it's only used to monitor cat function. I'm willing to bet that your closed loop fueling is a touch rich now with this code. Maybe AFR's in the mid 13's rather than stoich. Don't just block the code, fix it. The whole process of simply eliminating the ECU's ability to throw certain codes is a haphazard way of doing things, IMO. Far from a fix. Log some closed loop operation, and send the logs Doms way, as Kevin suggested.

I definitely wasn't going to ignore it. This is just another reason for me to buy an AFR meter

. Who can help me do some logging?

TheBigChill · « **Reply #4 on:** March 20, 2011, 12:04:51 PM »

Yeah, just saying. Wish I had a cable for ya. Phong has one, Styles does, I think Idipskoalmint does as well.

phong · « **Reply #5 on:** March 20, 2011, 01:38:24 PM »

I'm in Latham Wednesday night if you need to pull some logs.

zeedeveel55 · « **Reply #6 on:** March 20, 2011, 03:34:46 PM »

Quote from: phong on March 20, 2011, 01:38:24 PM

I'm in Latham Wednesday night if you need to pull some logs.

cool, but would you be willing to come to niskayuna?

phong · « **Reply #7 on:** March 20, 2011, 09:21:50 PM »

Yeah, I pretty much just twiddle my thumbs on the night in Latham every week.

Shoot me a PM on Wednesday.

zeedeveel55 · « **Reply #8 on:** March 20, 2011, 11:32:14 PM »

ok we'll figure it out, i dont mind driving to latham.

RedRoof2 · « **Reply #9 on:** March 21, 2011, 04:08:15 PM »

There is a huge troubleshooting section on this code in Mitchell. Suffice to say, BOTH front and Rear O2 sensors are only two steps out of 19 possibilities. Other items such as exhaust system leaks, MAF function, Coolant temp sensor, etc, are involved too.

zeedeveel55 · « **Reply #10 on:** March 21, 2011, 07:03:07 PM »

a thousand apologies for my stupidness my lord, but wtf is Mitchell?

gebby1029 · « **Reply #11 on:** March 21, 2011, 08:06:45 PM »

Mitchell is what a lot of repairs shop use for many things. One of which is telling the tech what steps to take when diagnosing a car given a specific code.

RedRoof2 · « **Reply #12 on:** March 22, 2011, 09:47:22 AM »

Quote from: zeedeveel55 on March 21, 2011, 07:03:07 PM

a thousand apologies for my stupidness my lord, but wtf is Mitchell?

Most of the time, it gives rather basic and stupid directions such as "Make sure the ignition switch is turned to ON before diagnosing engine noise". In this case, it brings forth some good info. System too Lean/Rich falls into the wonderful world of short and long term fueling. In this case, the Oxygen sensors play a part, but don't run the whole show. If you've got mileage on the car and want to take a shot from the hip, replacing both O2's is probably a prudent move anyhow. Otherwise, this could also be another sensor or circuit transmitting faulty data or having a problem with a short. Are there any other codes in memory or is this the only one?

zeedeveel55 · « **Reply #13 on:** March 22, 2011, 09:54:13 AM »

ive got a few hundred miles short of 50k, i don't know if that warrants enough mileage to worry about the o2 sensor, but the only other code i had from a while ago was a cylinder misfire, but that was taken care of with a new coil pack. other than that it's been ship shape.

RedRoof2 · « **Reply #14 on:** March 22, 2011, 10:01:11 AM »

Quote from: zeedeveel55 on March 22, 2011, 09:54:13 AM

ive got a few hundred miles short of 50k, i don't know if that warrants enough mileage to worry about the o2 sensor, but the only other code i had from a while ago was a cylinder misfire, but that was taken care of with a new coil pack. other than that it's been ship shape.

At 50k, normally O2 sensors aren't a concern unless they've been subjected to some sort of impact, like changing an exhaust. Hmmm. Probably a good idea to diagnose this one and make sure there aren't other items causing the issue.

zeedeveel55 · « **Reply #15 on:** March 22, 2011, 10:15:02 AM »

yea, im getting together with phong tomorrow to do some logs. i have also been keeping my foot out of it.

phong · « **Reply #16 on:** March 22, 2011, 11:46:26 AM »

Search on NASIOC returned, amongst a bunch of stupidity, a faulty rear sensor as the most common cause of that code. Could be an exhaust leak as well?

zeedeveel55 · « **Reply #17 on:** March 22, 2011, 11:54:02 AM »

Quote from: phong on March 22, 2011, 11:46:26 AM

Search on NASIOC returned, amongst a bunch of stupidity, a faulty rear sensor as the most common cause of that code. Could be an exhaust leak as well?

i saw that, that's why i wondered if i should just replace it. i also listened for an exhaust leak, but i couldn't hear/feel anything. but i will double check today.

TheBigChill · « **Reply #18 on:** March 22, 2011, 03:04:29 PM »

I had a tiny exhaust leak 4" before my rear 02 sensor (barely audible), and it resulted in a recurring CEL for "catalyst inefficiency". Eliminating the crack, eliminated the code, 2000 miles deep, and no CEL.

Because your rear 02 has more inherent functionality than mine, it very well could result in the code you're seeing. Like RedRoof said. Good luck !

zeedeveel55 · « **Reply #19 on:** March 23, 2011, 11:12:09 PM »

did some logs tonight, and everything looked fine. i dunno what the issue was. maybe the sensor is just on its way out. i dunno. ill post up a screen shot when phong emails me the results.

zeedeveel55 · « **Reply #20 on:** March 28, 2011, 03:31:16 PM »

CEL came on yesterday coming home from utica. wasn't goosing it or anything, just had the cruise at 74-75 was fine for 20 min then it came on. im assuming that it's the same thing, but im going to check it after work today. im not going to clear it this time, but i will need somebody's help in logging it again.

thanks in advance

Devin

zeedeveel55 · « **Reply #21 on:** March 28, 2011, 04:45:24 PM »

ok along with the P2096 code i got

P0137 02 sensor circuit low volts (bank 1 sensor 2)

im gonna check the wiring on it as this may be the leading cause of the problem.

Kavik · « **Reply #22 on:** March 28, 2011, 05:47:18 PM »

sounds like you were right in the first place, that the sensor needs to be replaced to start with

zeedeveel55 · « **Reply #23 on:** March 28, 2011, 06:02:09 PM »

and/or its just a wire. maybe ill just replace it. i dunno ill check for a loose end, if it's not there ill get one.

phong · « **Reply #24 on:** March 28, 2011, 06:06:47 PM »

Quote from: zeedeveel55 on March 28, 2011, 03:31:16 PM

CEL came on yesterday coming home from utica. wasn't goosing it or anything, just had the cruise at 74-75 was fine for 20 min then it came on. im assuming that it's the same thing, but im going to check it after work today. im not going to clear it this time, but i will need somebody's help in logging it again.

thanks in advance

Devin

If you want to log again I'm in town tomorrow night. I found the logs from last time, they don't really show much...especially since I was having a brain fart when selecting parameters.

So, has anyone actually determined whether or not the rear sensor in the EJ255/7 engines actually plays a larger role than in the EJ205/7 engines? If it doesn't, then it would be safe to disable the codes rather than wasting money on an "emissions only" sensor.

Author Topic: CEL P2096 (Read 1639 times)