O2 Sensor Fooling
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O2 Sensor Fooling
Gentlemen,
I got my RP Midpipe in today. Installed the O2 Sensor Fooler and the midpipe. Everything was going fine until about 3 hours later and I threw a CEL. Two questions for you guys.
1. Has anyone tried the O2 Sensor foolers on a RX-8 and had them working?
2. Anyway to get rid of this CEL? (Other than the dealer)
Thanks,
Slavearm
I got my RP Midpipe in today. Installed the O2 Sensor Fooler and the midpipe. Everything was going fine until about 3 hours later and I threw a CEL. Two questions for you guys.
1. Has anyone tried the O2 Sensor foolers on a RX-8 and had them working?
2. Anyway to get rid of this CEL? (Other than the dealer)
Thanks,
Slavearm
The RX8's catalyst monitoring is different from past Mazda models, due to the addition of a front linear oxygen sensor. Past systems monitored front & rear oxygen sensors to compare inversion ratios. This system uses a linear type sensor for fuel control (Front) and a conventional sensor for catalyst monitoring (Rear). The PCM will command the short fuel trim to change from rich to lean 30 times at a 1 HZ interval. This will induce the front oxygen sensor current to cycle from high to low at the same interval. The PCM then compares the waveform inversions of the rear sensor to determine catalyst deterioration. This makes it impossible to use conventional O2 sensor "foolers" to spoof the rear O2 sensor signal.
Originally Posted by Charles R. Hill
Like Jeff said, the foolers don't work. Like I am saying, if you want to use the catless midpipe then get used to the CEL.
CRH
CRH
It might be a hit-or-miss thing, but I have had a CAT-less midpipe on my car for about a year now and I've never had a CEL.
Then again, I've never had a CEL on my car for any reason unless I intentionally triggered one by over-limiting a sensor (or unplugging one altogether).
I can't say that I know why, exactly.
That is awesome. Nice engineering. I don't see why it works (restriction has nothing to do with the way the feedback system operates on the rear O2 sensor), but that doesn't matter.
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Originally Posted by GTAW
I now have a little over 250 miles without any CEL. I am sure the cel is not going to come back.....unless I modify something else on the car. :D
MazdaManiac......I designed a bushing that goes in between the 02 bung on the midpipe and the 02 sensor that, in short, mimicks the restriction that the cat would otherwise do. Instead of hacking into the wires of the sensor, I found it much easier to machine 304L stainless steel and "pull" out the sensor untill I found a "sweet spot" for it. I found that the tolerances have to be really close for the bushing to work, too far out and the CEL will still come back on. The piece turned out pretty nice which I added a copper crush washer to seal the bushing to the 02 bung. So I'm pretty happy with the results I've gotten so far.
Oh.....to get rid of the existing CEL, I used my AutoEnginuity Scan tool. After I put on about 300 miles, I will take out the bushing to get the CEL back on and reinstall the bushing to make sure the car will clear the cel after a few drive cycles. That way, people that don't have a way of clearing the check engine light won't have to worry.
MazdaManiac......I designed a bushing that goes in between the 02 bung on the midpipe and the 02 sensor that, in short, mimicks the restriction that the cat would otherwise do. Instead of hacking into the wires of the sensor, I found it much easier to machine 304L stainless steel and "pull" out the sensor untill I found a "sweet spot" for it. I found that the tolerances have to be really close for the bushing to work, too far out and the CEL will still come back on. The piece turned out pretty nice which I added a copper crush washer to seal the bushing to the 02 bung. So I'm pretty happy with the results I've gotten so far.
Oh.....to get rid of the existing CEL, I used my AutoEnginuity Scan tool. After I put on about 300 miles, I will take out the bushing to get the CEL back on and reinstall the bushing to make sure the car will clear the cel after a few drive cycles. That way, people that don't have a way of clearing the check engine light won't have to worry.
Originally Posted by TR1GGERx1
hey my friend was thinkin the same. u think this will work if i buy a 22mm spark plug non fouler and put it in between the o2 bung and the o2 sensor ? my friend di dit on his s2000 and also on a wrx and worked. im thinkin it would work for me as well?
Well, if you have the Greddy kit, you don't need to do any sort of RPM extraction.
If you are starting from scratch, Greddy now makes an RPM extractor module that is simple to implement.
The diodes are only necessary to condition the outputs of the E-Manage to control the ignition coils.
If you are starting from scratch, Greddy now makes an RPM extractor module that is simple to implement.
The diodes are only necessary to condition the outputs of the E-Manage to control the ignition coils.
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From: Europe
Originally Posted by GTAW
After reading my thread, I guess restriction isn't the best term to use, I know the cat can store about 3-5 seconds of oxygen at idle with a lean burning mixture.
Then, with a rich mixture the stored oxygen will be released. After the cat reaches it storage limit as well, causes the oxygen to be passed into the exhaust.
As the cat loses its ability to store and then release oxygen, the 3-5 seconds starts to decrease causing a current drift that increases quite dramatically. This then falls out of a predetermined range, giving you that lovely CEL and telling you that the cat is not functioning correctly. With out the cats... say, with a midpipe, it doesn't take long for the sensor to go crazy and trip the cel.
So, I was looking at it like a sponge, if you will, and would "soak" up so much oxygen, then ultimately releasing it slowly into the path of the second 02 sensor.
By making a bushing that brings the 02 sensor out at the right amount....(Sorry, an extra 02 bung welded or an antifouler, even in the right size and pitch doesn't work....I've tried it with my car and it lasted about 18 miles.....If you don't belive me, try it!)..... gives the sensor an atmoshpere that resembles a "stock" setup.
That was a crappy way to type that....oh, well. :p But, you get the idea!
Then, with a rich mixture the stored oxygen will be released. After the cat reaches it storage limit as well, causes the oxygen to be passed into the exhaust.
As the cat loses its ability to store and then release oxygen, the 3-5 seconds starts to decrease causing a current drift that increases quite dramatically. This then falls out of a predetermined range, giving you that lovely CEL and telling you that the cat is not functioning correctly. With out the cats... say, with a midpipe, it doesn't take long for the sensor to go crazy and trip the cel.
So, I was looking at it like a sponge, if you will, and would "soak" up so much oxygen, then ultimately releasing it slowly into the path of the second 02 sensor.
By making a bushing that brings the 02 sensor out at the right amount....(Sorry, an extra 02 bung welded or an antifouler, even in the right size and pitch doesn't work....I've tried it with my car and it lasted about 18 miles.....If you don't belive me, try it!)..... gives the sensor an atmoshpere that resembles a "stock" setup.
That was a crappy way to type that....oh, well. :p But, you get the idea!
Fabrice
Foolers don't work.....
These bushings don't work.
Even the "GTAW" person has not got it to work.
Nobody who has tried it has had a positive result.
It doesn't work for the Mazda Protege, where the idea originated, and it certainly won't work on the '8.
If you read the previous thread thru, you will notice that Mr. GTAW owns a ScanTool, that he uses to delete the CELs, which may explain why the bushing works SO well for him
.
The whole theory of the cat "storing oxygen to release later" is so far off as to be laughable
.
Some people have reported that after many CELs, they stop coming so frequently, but that is as good as it gets.
End of truthiness session!
S
Even the "GTAW" person has not got it to work.
Nobody who has tried it has had a positive result.
It doesn't work for the Mazda Protege, where the idea originated, and it certainly won't work on the '8.
If you read the previous thread thru, you will notice that Mr. GTAW owns a ScanTool, that he uses to delete the CELs, which may explain why the bushing works SO well for him
.The whole theory of the cat "storing oxygen to release later" is so far off as to be laughable
.Some people have reported that after many CELs, they stop coming so frequently, but that is as good as it gets.
End of truthiness session!
S
U-Stink-But-I-♥-U
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From: 12 o'clock on the Beltway.
I debated saying just what you just said but I thought it better that they learn for themselves. I think there is another thread where GTAW even said that the doo-hicky wasnt working any more.
I love truthiness. It is so much better than thinking.
FWIW my cat, in fact both of them, store oxygen to release later (think about it, it will make sence later.) They also store hair in their gut to release later, too. I just got done pulling, not five minutes ago, one of these special treats out between my toes after steping on it.
I love truthiness. It is so much better than thinking.
FWIW my cat, in fact both of them, store oxygen to release later (think about it, it will make sence later.) They also store hair in their gut to release later, too. I just got done pulling, not five minutes ago, one of these special treats out between my toes after steping on it.
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Modena
Joined: Oct 2004
Posts: 308
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From: Wentzville, MO
Originally Posted by StealthTL
These bushings don't work.
Even the "GTAW" person has not got it to work.
Nobody who has tried it has had a positive result.
It doesn't work for the Mazda Protege, where the idea originated, and it certainly won't work on the '8.
If you read the previous thread thru, you will notice that Mr. GTAW owns a ScanTool, that he uses to delete the CELs, which may explain why the bushing works SO well for him .
The whole theory of the cat "storing oxygen to release later" is so far off as to be laughable .
Some people have reported that after many CELs, they stop coming so frequently, but that is as good as it gets.
End of truthiness session!
S
Even the "GTAW" person has not got it to work.
Nobody who has tried it has had a positive result.
It doesn't work for the Mazda Protege, where the idea originated, and it certainly won't work on the '8.
If you read the previous thread thru, you will notice that Mr. GTAW owns a ScanTool, that he uses to delete the CELs, which may explain why the bushing works SO well for him
.The whole theory of the cat "storing oxygen to release later" is so far off as to be laughable
.Some people have reported that after many CELs, they stop coming so frequently, but that is as good as it gets.
End of truthiness session!
S
Sorry to say I run one of said bushings no cell sins 3500 miles.
Without the bushing the cell was on in less then 10 miles of driving the car.
Even the dealer could not find 1 error code stored in the cars ecu.
(Only fault they could find was the tire sensors, OEM tires and rims where replaced)
Have 4 fellow RX-8 drivers that can testify these results!
