Anyone make an O2 fooler for the rear O2 sensor in the B7 A4 yet?

[Jer]

Curious if anyone has done this yet and if so what the recipe is. Did some searching and didn't come up with much. I know if you do an ECU upgrade they have a way to disable this but I'm more curious if anyone has made their own ECU fooler device yet. Should be fairly simple and inexpensive for those who have done stuff like this before.

[b7ftw]

yeah, i just had it put on last week and havent gotten a CEL since... cost $50 (im not sure if it included shipping or not)... ive been driving with that annoying CEL for almost a whole year and LOVE not having it anymore!!!!

i dont recall the brand but can find out tomorow.

[Jer]

More information would be greatly appreciated. I know the Supra guys were doing this with a few bucks worth of parts so I'm curious what all of the options are out there.

[impretzle]

back in my subaru days we used 02 extenders which essentially placed the 02 sensor out of the heavy exhaust flow.
http://www.hho4fuelstore.com/oxygen-...-extender.html

[Jer]

back in my subaru days we used 02 extenders which essentially placed the 02 sensor out of the heavy exhaust flow.
http://www.hho4fuelstore.com/oxygen-...-extender.html

I saw where a few people were using a couple of these stacked with various size holes in them. Seems like a decent fix for about $10 if someone can post exactly how many they used and what sizes holes they selected/drilled.

[Tooney]

VAG it off or go Stage II....


......Go Stage II

say yes..yes

[Jer]

Well, I'm planning to run Stage II power using methanol injection on pump gas but the only question is if I'm going to spend $600 or so on an ECU flash or if I'm just going to get an electric boost controller for half the price and have more control over boost. If I go this route I would need something to keep from throwing CEL w/o a cat. I can just use a VAG to turn the 2nd O2 sensor off? Perfect answer right there. I should be able to run a boost controller and run ~14psi on 91oct and then whatever boost levels are used for the 100oct programs but run methanol injection. Still trying to decide if I need an ECU flash or not. So far I'm not coming up with any real solid reasons that would require it.

[Charles]

Two spark plug anti foulers. I can't remember the part number, but it's been posted in here, so maybe a search will pull it up. I didn't have to drill anything. The O2 sensor just threaded in and the foulers threaded into the bung on the test pipe. So far it's been about 3 weeks and no Check Engine for me.

[Jer]

I think people were using a brand called 'HELP' in a red/white package that come 2 to a pack. They were talking about drilling one of them with different sizes and what not but didn't draw any specific conclusions on that. Sounds like if I get a two pack and just use them both as is I will be good to go then huh? Since I'm getting a custom exhaust made it would be nice if there was a option to VAG it off since then I wouldn't even have to weld a bung in.

Two spark plug anti foulers. I can't remember the part number, but it's been posted in here, so maybe a search will pull it up. I didn't have to drill anything. The O2 sensor just threaded in and the foulers threaded into the bung on the test pipe. So far it's been about 3 weeks and no Check Engine for me.

[Grishbok]

Act as spacer to receed the O2 sensor probe out from the exhaust gases. By doing this, there will be less detectable oxygen at the sensor tricking the fuel computer into thinking it is more rich than it actually is. This manipulates the voltage from the O2 sensor to cause the injectors to pump less fuel leaning out the air:fuel mix. This results in a reduction in fuel consumption. Just by itself it can gain you up to 10% better MPG as it leans your fuel ratio.

mmmmmmm that sounds healthy.
Lean beef = ok
Lean engine = Bad

[Jer]

mmmmmmm that sounds healthy.
Lean beef = ok
Lean engine = Bad

In most vehicles the rear O2 sensor has no control over the A/F ratio and is only in place to monitor before/after cat converter to make sure it's functioning properly. The only time you would want to disable/fool the rear sensor is if you no longer have a cat to keep #'s in line.

[Grishbok]

correct! but now im in the mood for some 80% lean beef tacos.

[Jer]

correct! but now im in the mood for some 80% lean beef tacos.

Mmmm... tacos.

[Charles]

I think people were using a brand called 'HELP' in a red/white package that come 2 to a pack. They were talking about drilling one of them with different sizes and what not but didn't draw any specific conclusions on that. Sounds like if I get a two pack and just use them both as is I will be good to go then huh? Since I'm getting a custom exhaust made it would be nice if there was a option to VAG it off since then I wouldn't even have to weld a bung in.

I thought the drilling was for a BMW. I know the article that was linked, was for a BMW.

I'm pretty sure my exhaust guy didn't have to drill them out. I know I threaded them into the anti-foulers myself and I got about 3-4 turns before it stopped.

[Jer]

So basically you just stacked one inside the other, screwed in the O2 and then threaded the entire thing into the exhaust and it worked fine?

I thought the drilling was for a BMW. I know the article that was linked, was for a BMW.

I'm pretty sure my exhaust guy didn't have to drill them out. I know I threaded them into the anti-foulers myself and I got about 3-4 turns before it stopped.

[Jer]

I guess they have two variants in the 18mm non-fouler... a long taper and a short taper. Anyone know which one?

Ninja Edit: Looks like the HELP part number 42002 is the ones suggested for use with O2 sensors. Can anyone confirm this is indeed the case with this application?

[Msu2312]

im at a loss here, i have a cel and i hate it haha i have 2 anti fouleers part 42002 , they have been sitting in my room because i dont know if i have to drill them before putting them on the TP or just put them on the way they are or what.... can anyone shed some light on what exactly you are to do?

[Jer]

im at a loss here, i have a cel and i hate it haha i have 2 anti fouleers part 42002 , they have been sitting in my room because i dont know if i have to drill them before putting them on the TP or just put them on the way they are or what.... can anyone shed some light on what exactly you are to do?

I'm guessing it's more of a length of probe thing than anything else as far as the drilling goes. If you can seat the O2 sensor into one of them w/o it coming into contact with the bottom of the adapter then you shouldn't have to drill. I'm guessing drilling one out is to that the probe has room to clear the first one and thread in tightly.

Someone who has done this feel free to correct this if it's wrong.