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Hello all. I've had my 08 40th anniversary ed for about 4 months now. Love the car. I installed a bhr mid pipe on her last weekend. I also installed an o2 extension and reinstalled the o2 sensor. Now I've got cel codes p2270, p2096, p0139. Never had these codes before. I was getting a 4020 but that has not come back on since cat removal. I replaced plugs, wires, coils when I got the car and I do premix. Any thoughts?
Can you remove the extention? Those codes say the O2 sensor is reading too lean and not responding to mixture changes correctly, so probably it's not in the exhaust stream. Since it doesn't trust anything the sensor says, it doesn't set a P0420, but if you remove the extention, those codes will go away and likely P0420 will be set.
P0420 means your cat or rear O2 are bad. P0139 means you tried to fool the rear O2 using an anti-fouler or O2 extension and it didn't work because the PCM checks for that stuff.
P2270 is saying that the rear O2 is stuck with a lean condition, probably because of the antifouler (maybe you have a leak in there somewhere and a venturi effect is pulling air in?).
Remove the O2 extension and just install the rear O2 sensor normally. Clear your codes and see what comes back. If you only get P0420 (expected if you don't have a cat) then everything is fine. Try reinstalling the extension and pay particular attention to how well it seals. If you still get the P0139/2096/2270 then there may be something wrong with your O2 sensor, its wiring, or its connector. Verify those things.
Just keep in mind that if everything is working correctly, the extension should cause a P0139 code. A few people get lucky and don't get P0139 but don't count on it. If you want to run cat-less without any codes, you need to use a tuning solution to turn off cat health monitoring and throw the extension away (MazdaEdit, Versatuner, Cobb AccessPort).
Well I finally got around to removing the O2 spacer
, well most of it. I left the 3/4" extension on it. It's been two days with no codes so hopefully that did the trick.
Please assist.
My 2007 rx8 CEL came on today - P0420 code (only...reads something like efficiency below threshold Bank 1). I understand that P0420means your cat or rear O2 are bad. In the past 2 weeks Ive replaced the Coils Wires Plugs, while a shop put in a new Cat+pipe. The shop showed me what they ordered and installed was OE (original equipment) qualified part (...so I presume).
Since the shop didn't know how to reset the computer, I got the rx8 back and had to preform the 20x break pedal press to reset the computer. After the CEL cleared, I was able to drive it here-and-there this past week with no problems or CEL - until today. Perhaps they used the old-original O2 sensor (?) and it finally crapped out? Gosh I hope its not related to the new cat. pipe...Could the new cat. pipe throw a solid P0420 code? Thank you in advance.
Please assist.
My 2007 rx8 CEL came on today - P0420 code (only...reads something like efficiency below threshold Bank 1). I understand that P0420means your cat or rear O2 are bad. In the past 2 weeks Ive replaced the Coils Wires Plugs, while a shop put in a new Cat+pipe. The shop showed me what they ordered and installed was OE (original equipment) qualified part (...so I presume).
Since the shop didn't know how to reset the computer, I got the rx8 back and had to preform the 20x break pedal press to reset the computer. After the CEL cleared, I was able to drive it here-and-there this past week with no problems or CEL - until today. Perhaps they used the old-original O2 sensor (?) and it finally crapped out? Gosh I hope its not related to the new cat. pipe...Could the new cat. pipe throw a solid P0420 code? Thank you in advance.
If you paid less than $1k, I doubt it's OEM.
Did they show you that the cat they took off was bad?
The 2 pics I have of it on the rack are of the old cat pipe not the new (we were measuring heat readings)! No, they didnt show me the original cat...Regrettably, I know better-I should of asked for the old part back too (but I thought I was Good To Go). Now that I think of it, either they didn't know or they convinced me...for they called it an OE "direct fit". I recall they said something to the affect...It's a direct match, bolt-on, so less labor to weld pipes....and so on. It cost me around $560 in-total.
Im thinking about taking it back to that shop and ask them to put on a new O2 Sensor on it, to see if that clears the P0420 code. *I could not locate in schematics if the rx8 has one or two O2 sensors? Meaning, is there an upstream and downstream O2 sensor, or just one O2 senor (that throws the P0420) on the cat itself because only one manifold-to-exhaust pipe?
UnknownJinX: Did you have your "BHR mid-pipe + HJS Tuning cat" installed professionally? Gulp-what all that cost $2K? I cannot locate anything relating mazda rx8 to JHS on their website.
I know of the BHR "mid-pipe + cat assembly" but his cat does not come with a warranty; I need to pass emissions in Wisconsin. I hate to buy all that and then not pass immessions.
Ugh...Since the CEL came on yesterday and it operated normally driving home from O'Riellys, I drove it the 3.4 miles to work today, and it still operated responsively as it should...which perplexes me. Oh CEL why art thou - Go Away! Thank you all for chiming-in and further suggesting info on the (1 or 2) O2 sensor locations...I may just do it myself.
There is a front AFR(wide band) and rear O2(narrow band) sensor. The rear one attaches to the cat.
RX-8 cat assembly isn't welded on. It's sold as one unit with the resonator. It's bolted to the exhaust manifold and catback.
This is what the OEM unit should look like.
As for my combo, yeah, it's hideously expensive. I had a shop install it because they have a lift, but the installation doesn't cost much. I haven't got a P0420 CEL and it has been a year. Not 100% sure it will pass a sniffer test, though.
Last edited by UnknownJinX; 08-28-2018 at 10:05 PM.
Whatever they put in ,its not a Mazda cat. Rather than telling them what to replace at your own expense, let them diagnose their own work. These things come with warranties.
Personally, it sounds like the new cat isn't up to the job its given, and/or whatever killed the old cat killed this one too, meaning you have a problem upstream. Ignition coils, for example.
Whatever they put in ,its not a Mazda cat. Rather than telling them what to replace at your own expense, let them diagnose their own work. These things come with warranties.
Personally, it sounds like the new cat isn't up to the job its given, and/or whatever killed the old cat killed this one too, meaning you have a problem upstream. Ignition coils, for example.
Thank you. Ya- its all messed up Allow me to clarify: In-person, they said they could do the work (they previous did a break job so they knew it was a rotary). When they got the rx8, they diagnosed and determined to replace the cat pipe. Then they refused to do any more work (Clear the codes because its a rotary they said!). They gave it back to me with the CEL still on! Then I replaced the coils/wires/plugs, cleaned all ELE contacts, ess...all that good stuff. Then I cleared the codes (20 break-push), and the CEL went away! I drove it lightly for 5-6 days then the CEL P0420 came on. Since it has about 100K miles and they didn't suggest or replace the O2 sensors...Im thinking one or both original O2s are shot and throwing the P0420 code, Bank I. So I think I may start with ordering the upstream O2sensor 1st. Other than that, the rx8 drives normally revving thru gears coming up to speed and maintaining speed (doesn't cough or sputter).
Its Friday morn and I finally got the rx8 home in the garage, jacked it up and located the upstream/downstream sensors...Now time to place an order!
Thank you. Ya- its all messed up Allow me to clarify: In-person, they said they could do the work (they previous did a break job so they knew it was a rotary). When they got the rx8, they diagnosed and determined to replace the cat pipe. Then they refused to do any more work (Clear the codes because its a rotary they said!). They gave it back to be with the CEL still on! Then I replaced the coils/wires/plugs, cleaned all ELE contacts, ess...all that good stuff. Then I cleared the codes (20 break-push), and the CEL went away! I drove it lightly for 5-6 days then the CEL P0420 came on. Since it has about 100K miles and they didn't suggest or replace the O2 sensors...Im thinking one or both original O2s are shot and throwing the P0420 code, Bank I. So I think I may start with ordering the upstream O2sensor 1st. Other than that, the rx8 drives normally revving thru gears coming up to speed and maintaining speed (doesn't cough or sputter).
Its Friday morn and I finally got the rx8 home in the garage, jacked it up and located the upstream/downstream sensors...Now time to place an order!
Drop the cat and inspect it to be sure before you start.
P0420 has little to nothing to do with sensors, it's very specifically the cat. Drop the cat and face the music.
Loki, you've save my *** several times in the past and I value your opinion. My question is... I have a midpipe and i was getting p0037. So I replaced the downstream O2 sensor. After several days of no CEL, now I have the p0420. What's so strange is that my car runs very sluggishly like it would if it had a bad cat. Just curious as to your thoughts. As always, thanks for your help.
It sounds like you had a broken sensor (P0037), and after you replaced it the new sensor started reading an actual cat problem (P0420). The cat problem may have existed before, but since the sensor was broken, there was no way to know.
I'd stop driving and drop that cat to inspect & replace. Especially if it's noticeably sluggish, the cat would have to be in pretty bad shape, or your ignition is severely degraded which will kill your cat in short order. Either of the above will kill your engine in short order, so ... yeah.. I'd stop driving.
It sounds like you had a broken sensor (P0037), and after you replaced it the new sensor started reading an actual cat problem (P0420). The cat problem may have existed before, but since the sensor was broken, there was no way to know.
I'd stop driving and drop that cat to inspect & replace. Especially if it's noticeably sluggish, the cat would have to be in pretty bad shape, or your ignition is severely degraded which will kill your cat in short order. Either of the above will kill your engine in short order, so ... yeah.. I'd stop driving.
That's the thing though... I have a midpipe (no cat).
07-25-2018, 08:32 AM
