DIY Mechanical O2 simulator
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From: Boise, Idaho
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DIY Mechanical O2 simulator
Ive been asked about how to do this process on more than one occasion and have been happy to supply the information. Hopefully someone will add this to the FAQ on turbos to help save some members some time ......
These are NOT my photos but im unsure of who the owner is exzactly. But they do give some very good photos and i hope that they dont mind
You now need to drill out 1 of the non foulers using a 1/2" drill bit. When finished this is what it will look like.
o2 Sensor inserted in the modified non fouler
Second, unmodified non fouler now installed on modified non fouler, then threaded into the downpipe
These are NOT my photos but im unsure of who the owner is exzactly. But they do give some very good photos and i hope that they dont mind
You now need to drill out 1 of the non foulers using a 1/2" drill bit. When finished this is what it will look like.
o2 Sensor inserted in the modified non fouler
Second, unmodified non fouler now installed on modified non fouler, then threaded into the downpipe
?
i know its sorta a pre-post 
Thread Starter
Joined: Nov 2003
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From: Boise, Idaho
Rep Power: 327 Nahhh, you were just the more recent person to ask 
But if we can get a mod to add this to the FAQ it will save people time i hope
But if we can get a mod to add this to the FAQ it will save people time i hope
Originally Posted by drunkenmagnum
awsome! i think i am the member that finally pushed him over the edge!
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From: Boise, Idaho
Rep Power: 327 The second O2 sensor NOT the first!
Originally Posted by Pedro Lopes
You do this to the first 02 sensor right ( The one before the cat).
Thread Starter
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From: Boise, Idaho
Rep Power: 327 it restricts the amount of exhaust that gets to the second o2 sensor. This gives it a higher AFR reading. This simulates the cat doing its job when its not there
Originally Posted by v8eaterokv6
so what does this do exactly or how does it work
THE LONE STAR STATE
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From: Fort Worth, Texas
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Originally Posted by nick95673
how does this work? It just picks up less emmission gasses since its further back?
Very GOOD Post!!!! I have done the same thing with mine. I have been threw two state inspections and has lasted a year and a half. I have that Megan Racing down pipe by the way. Great job!
texascivic2k1
so now lets say i do this, could it potentially cause tuning issues because the ecu is reading incorrect data and adjusting a/f ratio off of it, or does the ecu only adjust a/f according to the first o2 sensor?
i think im gonna try it.
i think im gonna try it.
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From: Boise, Idaho
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Originally Posted by ncirom2003
so now lets say i do this, could it potentially cause tuning issues because the ecu is reading incorrect data and adjusting a/f ratio off of it, or does the ecu only adjust a/f according to the first o2 sensor?
i think im gonna try it.
i think im gonna try it.
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From: Rockville, Maryland
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Originally Posted by nighthawk1903
I Have 3 02 Sensors so i use this on the 2nd one, before the cat, and the third one after the cat right????
Registered!!
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From: Williamsburg
Rep Power: 0 I have a HX with a EX header an testpipe conversion now my header has 2 02 sensors top an bottom.an my cat has one after, my stock manifold had a honeycomb like resonator on it i might get some pics if need be,an the cat had one, so i have 1 02 bypass in the testpipe check engine light (STILL ON)..... I didn't drill it out could this be why???? an what would happen if i put it on the lower 02 sensor ????????/
Thread Starter
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From: Boise, Idaho
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Originally Posted by nighthawk1903
I have a HX with a EX header an testpipe conversion now my header has 2 02 sensors top an bottom.an my cat has one after, my stock manifold had a honeycomb like resonator on it i might get some pics if need be,an the cat had one, so i have 1 02 bypass in the testpipe check engine light (STILL ON)..... I didn't drill it out could this be why???? an what would happen if i put it on the lower 02 sensor ????????/
First O2 sensor in manifold closest to the cyl head
Second O2 sensor further down pipe , past cat converter( if you have one )THIS IS THE ONE THE FOULERS SHOULD BE ON AND YES IT MUST BE DRILLED OUT OR THE O2 SENSOR WOUNT FIT IN IT!
Third O2 sensor.........
Unless its a wideband i have NO idea what your talking about 
Joined: Mar 2003
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From: Houma, Louisiana
Rep Power: 304 What are they going to do? Only way to remove a CEL is to fix the problem or trick it into thinking you fixed the problem which this does. You could go with the AEM EMS which you can disable ob2 completely.
I would like to do this mod myself but I'm limited to space where my downpipe is. Anybody got an idea on how I could make an angled part fit with the same purpose?
I would like to do this mod myself but I'm limited to space where my downpipe is. Anybody got an idea on how I could make an angled part fit with the same purpose?
