Q for those w/ o2 bung welded in after second cat for CEL

[Keyan]

I am getting an o2 bung welded in after the second cat to get rid of the dreaded CEL because of my headers.

My question is for those who have sucessfully gotten rid of the CEL this way....

How far in inches past the second cat did you have the bung welded in? Ex: 3 inches, 4 inches, 2 and a half inches...

:confused: :confused:

Thanks.

[KeWLKaT]

mine is 3 inches away.

and no more cel w00t :)

[BColeman]

It was originally said to place it 14 inches from the end of the second cat. That's approximately the distance it was from the 1st cat.

It's on this site somewhere, I'm just too lazy to look for it for you...

[KeWLKaT]

Keyan I went to check, it's more like 5-6 inches!

[Keyan]

I just searched and I found some people are saying 6 inches. I might end up doing that.

[KeWLKaT]

i'd say it depends on the brand of cat more than the distance...

[Keyan]

well it's an oem secondary cat welded onto the headers...

[KeWLKaT]

ah! hmmm doesnt that defy the purpose though.... OEM cat....

[Keyan]

ah! hmmm doesnt that defy the purpose though.... OEM cat....


purpose of what? the headers and the restriction at the cat?

yeah, the stock midpipe was welded onto the headers by their first owner. I will fix it later when i get the money but the second o2 bung goes on the catback, so might as well do it and get rid of the cel anyway.

[2loud2k2xd]

i also heard of it being 14" away from the 2nd cat.

[bfgoedeke]

Has anyone considered running a O2 simulator on the #2 sensor. I'am running one on my 98 dodge. About 1K in miles and no cel. ( because I hammered out the cat anyway)

[Cypher]

reece (arunsenior04) is and his hasn't come on for awhile.

[Jonny666]

If you look at the stock system your primary cat is at the front of the motor, then the manifold curves down below your motor and the seccondary O2 sensor is behind the motor. that's a heck of alot more than 6 inches. I put mine as far back as i could without running into the resonator on my catback. Mine ended up being about 10 inches or so i belive. People have however had good results with about 6 inches or so. I would say you are in good shape anywhere from 6-10 inches.

[KeWLKaT]

Mine is good right now still, but I will be attempting an experiment to determine the difference in resistance between those two O2 sensors, on a stock car. This way, I will know what resistor to put in between them to achieve the -4% that the ECU should be seeing.

[Jonny666]

That would be incredibly good information to have.

[Toecutter]

Click Here (http://www.elantraxd.com/forums/showthread.php?p=228233#post228233)

[slow 2K2GT]

Dmdicks mentioned that an 18mm sprak plug non fouler on the 2nd o2 sensor would work, I know its been brought up here before but it seems that its been given less of a chance then the variying distances for the o2 sensor.

[Jonny666]

Dmdicks mentioned that an 18mm sprak plug non fouler on the 2nd o2 sensor would work, I know its been brought up here before but it seems that its been given less of a chance then the variying distances for the o2 sensor.

Its true, it may work. but to me it seems more like a band-aid than a fix. The problem that i've seen with O2 sensor simulators and spark plug defoulers is that they simply don't work for everyone. Every month or so you see someone on these boards with the thread that says "my [spark plug defouler / O2 simulator] worked for 3000Km and now it doesnt work, what's wrong with it?" I've only seen a couple where people moved the O2 sensor to behind the cat and most of them can be chalked up to not extending the wires properly.
example: check post # 7 in this thread
http://www.elantraxd.com/forums/showthread.php?t=19637