p2096 problem with catted DP

[Tommy]

I'm not sure what has caused the problem to be honest but I recently got this code when cruising at about 65 in 6th gear. I cleared it out only to get it again two days later, again, just cruising in 6th gear. This came maybe a month after the catted dp install so I'm not sure if this is the problem or not. Has anyone else had this happen with this mod? Only other performance mods I have are the MS CAI w/ straightener and the Cp-e TIP. Stock tune. Any help or suggestions are greatly appreciated.

[dMuze]

read through this.
Check Engine Light (P2098)
i know the code is a bit dif but its a place to start. cold weather also leans out trims

[www.cp-e.com]

That is actually a pretty comprehensive thread. The P2096 fault code basically identifies that the rear (post-cat) oxygen sensor is reading irregularly low voltage (or a lean condition, same thing). On newer cars the rearward oxygen sensor is actually also responsible for fuel trims, along with the forward sensor.

It would be helpful to see a log of your rearward oxygen sensor, relative to your forward sensor, to see if we can identify a problem with the sensor, or if the cat is plugged.

Sander

[Tommy]

Originally Posted by dMuze read through this. Check Engine Light (P2098) i know the code is a bit dif but its a place to start. cold weather also leans out trims

Thanks for that. I read through it and it did not seem like anyone found a real solution to this. FWIW, this did happen pretty soon after the temps dropped significantly here.

Originally Posted by www.cp-e.com That is actually a pretty comprehensive thread. The P2096 fault code basically identifies that the rear (post-cat) oxygen sensor is reading irregularly low voltage (or a lean condition, same thing). On newer cars the rearward oxygen sensor is actually also responsible for fuel trims, along with the forward sensor. It would be helpful to see a log of your rearward oxygen sensor, relative to your forward sensor, to see if we can identify a problem with the sensor, or if the cat is plugged. Sander

Sander, unfortunately, I do not have any monitoring devices. Is there anything I can try to fix this?

[SilverDemon]

Originally Posted by Tommy Thanks for that. I read through it and it did not seem like anyone found a real solution to this. FWIW, this did happen pretty soon after the temps dropped significantly here.

The solution was to get rid of the bung that the 2 manufactures were putting on the DP and replace it with a bung that was 90* to the exhaust flow.

The logs that were posted in that thread were the voltage readings from the 2nd O2 sensor. Mine had the sensor already set at 90*(with a 1" extension on the bung) to the exhaust flow, and smitty's was set at an odd angle to the exhaust flow. My sensor readings came back with a rang of .2v - .9v depending on the load of the engine, smitty's car came back with a reading .0v - .9v, again, depending on the load of the car.

It seemed that anytime the O2 sensor reading would drop below .2v after the car is up to normal operating temp, it would throw the P2196 code. In turn the ECU would dump more fuel to help warm up the cat. causing mileage to suffer, fuel trims to act up, and the closed loop AFR's to run extremely rich.

The only CEL (to my knowledge) that smitty is seeing is the P0421 inefficient cat. which hurts nothing to the performance of the car.

I mentioned this in the other thread that wrapping the area around and including the sensor with some heat wrap might help out, but this is just an idea for a short term fix........

[Tommy]

Originally Posted by SilverDemon The solution was to get rid of the bung that the 2 manufactures were putting on the DP and replace it with a bung that was 90* to the exhaust flow. The logs that were posted in that thread were the voltage readings from the 2nd O2 sensor. Mine had the sensor already set at 90*(with a 1" extension on the bung) to the exhaust flow, and smitty's was set at an odd angle to the exhaust flow. My sensor readings came back with a rang of .2v - .9v depending on the load of the engine, smitty's car came back with a reading .0v - .9v, again, depending on the load of the car. It seemed that anytime the O2 sensor reading would drop below .2v after the car is up to normal operating temp, it would throw the P2196 code. In turn the ECU would dump more fuel to help warm up the cat. causing mileage to suffer, fuel trims to act up, and the closed loop AFR's to run extremely rich. The only CEL (to my knowledge) that smitty is seeing is the P0421 inefficient cat. which hurts nothing to the performance of the car. I mentioned this in the other thread that wrapping the area around and including the sensor with some heat wrap might help out, but this is just an idea for a short term fix........

So you are saying this is a bad design on cp-e's part?

[SilverDemon]

A great design on the down pipe.....they just might of looked a little closer at where the bung was located in the exhaust flow, or maybe when the testing was done on the shop car it was an extremely hot summer day and the sensor never dropped below the .2v Too many variables to know what exactly went on. Hell, it could have even been that Mazda changed manufactures of the sensors from the time CP-E bought their shop car to the time a few of you guys are having the problems.

[dMuze]

unfortunately no company will promise a product wont throw a cel. im not sure if you are gen1 or 2 but it seems with the 2's that catted dp's dont require an extended or angled bung. they work just fine with the rear sensor directly in the exhaust stream. some non-catted pipes benifit from extended bungs or defoulers since they allow the rear sensor to see a change in temp. im not saying its a bad design, it clearly works for most gen1's, but gen2 is still a newer platform and companies are working the kinks out. i believe UR may actually be changing their bung setups on catted pipes.

[Tommy]

I can not remember the angle on the cp-e bung - anyone know? Also, where can I get soem heat wrap to give that a try?

[SilverDemon]

http://www.jegs.com/webapp/wcs/store...rm=header+wrap

[smitty5788]

Yes Im saying it was a bad design, same thing I said in the linked thread. Its Custom Performance ENGINEERING ... key word there and any engineer will know a fluid isnt going to turn a corner and go the direction oposite of the main flow into a dead end. Thats why at high load with high levels of exhaust flow the O2 sensor would cool down and exhaust wouldnt travel up the bung.

So if you catted pipe bung was like my catless one it is extended about 4 inches back up towards the turbo.

That being said, it may be that the Gen2 is different but I beleve Tommy had a Gen1 so I guess not that much different. And CPE has been told, weather they fix it is another issue.

[Tommy]

Yes, I'm in a 2007 Gen1. I'm going to try to get under the car tonight and look to see how the bung is set up on the catted cpe dp.

[smitty5788]

If it is longer than about an inch I can bet thats your problem unless you actually have a bad sensor. Check for leaks at the sensor and the DP while your under there.

[Tommy]

WIll do, the cig test works for me

[smitty5788]

haha there ya go man ... i prefer smokeless so i didnt try that one.

[Tommy]

Ya know, Sander, you could save me some of the trouble here and just tell me how your current catted dp (just bought mine at the last dyno meet) has the bung installed. At 90°?

[www.cp-e.com]

Originally Posted by Tommy Ya know, Sander, you could save me some of the trouble here and just tell me how your current catted dp (just bought mine at the last dyno meet) has the bung installed. At 90°?

Tommy, I'll be in the office on Thursday. I'll look at the design then, and take a few test logs on the test car we have here and try to possibly identify where the problem you are having is coming from.

Sander

[Tommy]

Thanks. What kind of damage am I doing to my car in the mean time by driving around with this CEL? Anyone know?

[dMuze]

no real damage running rich...stay off the WOT driving. it will just make you hatch and plugs filthy...and your mpg will suck

[Tommy]

Originally Posted by www.cp-e.com Tommy, I'll be in the office on Thursday. I'll look at the design then, and take a few test logs on the test car we have here and try to possibly identify where the problem you are having is coming from. Sander

It's Thursday! I hope to hear from you on this soon. I did not get a chance to get under my car yet due to the crap weather. Thanks.

[www.cp-e.com]

Hey Tommy,

Sorry about this, I've been very busy with stuff here. I promise I'll get some pictures tomorrow and ask the manufacturing guys about it.

Thank you,

Sander

[www.cp-e.com]

It is at 90 deg. This shouldn't really be an issue. I've put in a request to the mechanical side for an evaluation on this, I'll report back when I hear what they have to say.

Still could be a sensor issue though. And, try to avoid running around town running overly rich. This can in-turn destroy the catalyst.

[Tommy]

Originally Posted by www.cp-e.com It is at 90 deg. This shouldn't really be an issue. I've put in a request to the mechanical side for an evaluation on this, I'll report back when I hear what they have to say. Still could be a sensor issue though. And, try to avoid running around town running overly rich. This can in-turn destroy the catalyst.

I confirmed the same mysel;f just now - it is at a 90 degree angle and short too. I also discovered that the sensor nut itself is loose. Anyone want to confirm for me that this would be enough to cause this problem?

[dMuze]

if its so loose that gas is escaping then maybe it could cause an issue...starting to think the sensor may be bad though.

[Tommy]

Well, after PM'ing SD, he pretty much made me feel my gut is right and when I say it was loose, I mean I got a few turns on it by hand. The fact that it was that loose and I was getting this code says to me to go the simple route and just tighten the sumbitch. The sensor being bad and being loose would just seem too out there for me.

[dMuze]

yup...tighten, reset and drive for a day...hopefully all is well. would def be the end of a headache for you and the cheapest fix!

[Tommy]

Originally Posted by dMuze yup...tighten, reset and drive for a day...hopefully all is well. would def be the end of a headache for you and the cheapest fix!

By any chance do you know if it is a 22mm or what size it is? Very tight space so I will need some kind of short to get in there.

[dMuze]

its a standard o2 socket. if the bung is too long you may be better off with a set of channel locks or vice grips...just dont go too tight, and use anti-seize

[www.cp-e.com]

7/8ths or 22mm is standard oxygen sensor hex sizes.

[smitty5788]

Glad you figured it out, one of the things to check from the service manual for that code is a leak between the O2 sensors so I bet the loose sensor is the issue. If that doesnt fix it I bet its the sensor itself.

[Tommy]

Well, so far so good but it may take more than the 40 miles I put on since reset to get the CEL to go again. Anyone have any clear pics of the harness the o2 sensor plugs into an how it unplugs? I am pretty sure I am twisting the wire more than I would like and just thought it best to unplug before tightening.

[smitty5788]

On the gen2 the clip is on the drivers side of the plug if that makes sense. Its a pain to get to from under the car but its really easy if you remove the battery box. It sits on a bracket right under the inlet pipe.

[Tommy]

Ok, so I have not been able to tighten it yet with anything other than my hand so far. I have since put 124 miles on it in the save driving conditions and no CEL. I'll put another 100 miles on it tonight and if I still see no CEL, I think it's safe to say that the problem has been identified and fixed (or will be fixed when I properly tighten it.)

[www.cp-e.com]

Good, thanks for reporting back on the issue.

Sander

[Tommy]

Well, the CEL came back after 220 miles. At this point, I will assume that the hand tightened o2 sensor came loose again. I will confirm it is the same code tonight, clear it and hopefully tighten the o2 sensor down again with a proper wrench.

[Tommy]

Ok, so I pulled the codes with the Advance Auto scan tool and it turns out I had 5 codes in there:
p0420 - Catalyst efficiency below threshold bank
p2181 - Engine cooling system perform?
p0300 - random/multiple cylinder misfire detected
p0304 - cylinder 4 misfire detected
p0301 - cylinder 1 misfire detected

ANy ideas? Related to the o2 sensor being loose? Shoudl I start a whole new thread?

[Tommy]

Anyone have any ideas on these other codes? I will be under the car tonight to check to see if the o2 sensor backed out again and to properly tighten it with the right tool. Could a loose o2 cause any of these other issues? The cooling one really has me worried.

[dMuze]

sry man i havent seen those before

[Click Here]

Originally Posted by Tommy Anyone have any ideas on these other codes? I will be under the car tonight to check to see if the o2 sensor backed out again and to properly tighten it with the right tool. Could a loose o2 cause any of these other issues? The cooling one really has me worried.

It looks like first, your cat isn't performing as it should, which implies that it is failing, or simply wasn't ever efficient enough to pass the ECU's emissions checks (P0420).

Second, I think the loose O2 sensor may have caused other problems like an overly rich condition maybe fouling the plugs and causing a misfire. If the sensor was loose and was registering oxygen coming in from a leak, it may have caused the car to run rich and foul the plugs.

The cooling system code may have been a fluke, but I would start by monitoring what your engine coolant temps do while you're driving around. It may be a simple problem.

[Tommy]

Plugs are pretty new too. What shoudl I use to clean them, assuming they are fouled? Wire brush?

*edit*
I have brake cleaner and MAF cleaner. Will either of them clean plugs?