Page 1 of 1

O2 Sensor on Exhaust

Posted: Wed Jul 13, 2005 12:11 pm
by WRXWagon2112
A side-effect of my trip to Don Beyer today is the confirmation that the CEL I've experienced intermittently for the last couple years is in fact caused by the TurboXS turbo-back exhaust that I have (as I suspected).

What are the options to relocate / modify the sensor to avoid the error code? Any suggestions? I seem to recall some solution being the use of a spacer to "pull" the sensor out of the air stream. Anyone know where to get one of these spacers?

--Alan

Re: O2 Sensor on Exhaust

Posted: Wed Jul 13, 2005 12:26 pm
by Sabre
WRXWagon2112 wrote:A side-effect of my trip to Don Beyer today is the confirmation that the CEL I've experienced intermittently for the last couple years is in fact caused by the TurboXS turbo-back exhaust that I have (as I suspected).

What are the options to relocate / modify the sensor to avoid the error code? Any suggestions? I seem to recall some solution being the use of a spacer to "pull" the sensor out of the air stream. Anyone know where to get one of these spacers?

--Alan
I've heard of sparkplug spacers doing the trick and there is always the resistor fix. Definitely do a search on NASIOC :)

Posted: Wed Jul 13, 2005 2:03 pm
by Mr Kleen
an AccessPort will fix it. :wink: but just make sure the AP has the 1.30 maps loaded already. for some reason I can't get my AP to load the new 1.30 maps... :roll:

Posted: Sat Jul 16, 2005 12:07 pm
by zaxrex
The "Mechanical Fix" method of using spark plug anti foulers (NASIOC) wll get the O2 sensor out of the direct flow. I previously had a Pony Express MIL eliminator soldered onto the ECU wiring to get rid of the cat inefficiency code. Problem with that and other resistor or cap fixes is that some ECUs won't complete the diagnostics on the emissions or O2 monitoring system. That might not be a problem for some people, but if you have to get an emissions test and they read the OBDII port, you won't pass b/c the system tests are incomplete.

The anti-fouler plugs step around this and let the ECU complete its diagnostics. One drawback of using them is corrosion. I was driving Thursday and had the CEL come on. I was playing with different fuels and trims, so I thought it was that. Turned out to be P-0136 (IIRC) which is an indicator of the O2 sensor having problems. I cleared the code, but then it came back. I got under the car and unscrewed the sensor along with the mechanical fix. The "spacers" were heavily corroded and flakes of rust were all around the O2 sensor. I tapped the sensor to remove the rust and put it back on the TXS cat pipe. Code went away.

I think that the rust flakes had gotten in to the sensors screen and caused abnormal readings of the sensor as the resistance of the substrate was changed by the physical contact of the rusted metal flakes.

The ECU passed all emissions and O2 sensor tests, and I took it in for VA Safety and Emissions testing. With the fuel mix that I had in there, I didn’t even need the water injection to pass the inpection.

Posted: Sat Jul 16, 2005 12:28 pm
by WRXWagon2112
^^ Well, that pretty much seals it. I'm going to try the spacer fix. Time to do some searching in NASIOC for the right parts, etc.

--Alan

Posted: Sat Jul 16, 2005 1:10 pm
by zaxrex
http://forums.nasioc.com/forums/showthread.php?t=424666 look at post #22 on down. If you want to see them or test out my rusted ones call me at NOVA.403.9659 and we can meet up this afternoon and I can bring my tools.

Posted: Sun Jul 17, 2005 11:46 am
by schvin
zaxrex wrote:With the fuel mix that I had in there, I didn’t even need the water injection to pass the inpection.
curious, what did you use?

Posted: Sun Jul 17, 2005 12:13 pm
by zaxrex
89 octane, e-85, & 50/50 mix of methanol and distilled water.

Posted: Mon Jul 18, 2005 10:52 am
by Sabre
schvin wrote:
zaxrex wrote:With the fuel mix that I had in there, I didn’t even need the water injection to pass the inpection.
curious, what did you use?
Haha, I love that avatar... A friend had shown me that last week and I had thought of using it :)

Posted: Tue Jul 19, 2005 4:14 pm
by drwrx
Just in case anyone ever needs to pass the "sniffer" test in VA and you don't have access to e-85 or methanol. Try this:
Fuelon Power: www.fuelon.com
This is how I passed with one hi-flow cat.
Run your tank down to about 1/4. Add at least twice as much fuelon as it says (it has a measuring section w/ 1, 2, 3, 4, I throw in at least 2-3)
Let it mix with the gas for about a day.
Run the car for about 1/2 hour to get it nice and hot a.k.a. get the cat to light on.
Go get emissions done.

These were my readings back in march of '04:
Idle:
HC ppm: 56 / 110 limit
CO%: .00 / .75 limit
dilution 14.9

2500 RPM
HC ppm: 18 / 110 limit
CO%: .00 / .17 limit
dilution 15