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Anti fouler drilling
#1
Posted 26 April 2010 - 06:47 AM
It was mentioned that one needs to drill out the anti fouler for the O2 to fit (I havee allready bought the parts and confirmed this).
So my question is this: Do I drill it out just enough for the O2 "nozzle" to fit into the fouler and leave the small hole at the end still intact. Or do I drill the whole thing through and have it be one big opening?
Thanks in advance.
Doug.
#2
Posted 26 April 2010 - 10:19 AM
Ok so I am going to try the anti fouler trick. Allready replaced the rear O2 and was good for about a month.
It was mentioned that one needs to drill out the anti fouler for the O2 to fit (I havee allready bought the parts and confirmed this).
So my question is this: Do I drill it out just enough for the O2 "nozzle" to fit into the fouler and leave the small hole at the end still intact. Or do I drill the whole thing through and have it be one big opening?
Thanks in advance.
Doug.
the pics i have seen show 2 anti foulers used on the rear, the first one , threaded into the exhaust is left in tact, no changes. the second one , threaded into the first is drilled through completely. it appears as thought the tip of the o2 is longer than the anti-fouler so it extends part way into the first one. this setup puts the o2 sensor in its own small compartment with a very small opening into the exhaust .
please correct me if i'm wrong.
#3
Posted 26 April 2010 - 11:47 AM
GD
#4
Posted 26 April 2010 - 12:41 PM
When I've done it I only use one - drilled completely through. Works fine.
GD
that would certainly make it easier to mount, clearance wise.
#5
Posted 26 April 2010 - 01:58 PM
Stacking 2 is a waste of time, I've seen cars with NO cats working fine with just one.
Replace the front 02 sensor while you're there, if you did the rear one, the front one's not far behind. Potentially better MPG and cleaner running could result.
#6
Posted 26 April 2010 - 10:17 PM
#7
Posted 27 April 2010 - 09:15 PM
Replace the front 02 sensor while you're there, if you did the rear one, the front one's not far behind. Potentially better MPG and cleaner running could result.
This is in hopes that it will fix the re-accuring 420 code. It is for a "customer" and since he allready paid me for the O2 job I am throwing this in as a freebee. So I don't want to replace the front unless that code pops.
MPG and clean emissions is not a problem with it...yet.
#8
Posted 04 October 2012 - 07:34 PM
#9
Posted 04 October 2012 - 07:41 PM
Perhaps someone remembers the size, I think it's 17mm.
They come 2 to a package.
#10
Posted 04 October 2012 - 08:14 PM
#11
Posted 04 October 2012 - 10:41 PM
18mm is the size. Above is the link to Autozone part. Comes 2 in a pack for about $5.
NOTE: As I and others have discovered, this doesn't work on MY 2005+

#12
Posted 05 October 2012 - 08:01 AM
#13
Posted 05 October 2012 - 08:07 AM
#14
Posted 05 October 2012 - 09:40 AM
18mm flat washer anti-fouler Help brand 42009
#15
Posted 05 October 2012 - 12:32 PM
http://www.ebay.com/...aac418c&vxp=mtr
They work better, fit better, and no drilling involved. Much easier for me.
GD
#16
Posted 06 October 2012 - 01:27 PM
-The sensor requires a 22mm wrench to remove/reinstall. I didn't trust my adjustable at the weird angle so I went and bought 3 different sizes 20-22mm. I got lucky that i got the right one and saved another trip.
-a little penetrant and it came right off. Lucky me I guess. My Tacoma o2 sensor was not that easy a few years ago
-After I got it loose i went to unplug from under the hood and saw that I could reach the sensor easy as could be from above instead of wrapping my arm around the exhaust pipe. Shame on me for not looking. It went back in a lot easier.
I have a drill press and the anti fouler was cake to drill through.
I'm driving to MA for a wedding tomorrow so we'll see if it worked. I'll update with the results and thanks for all the help
Update: I started the car a few hours after posting the above and check engine light was on. I had the negative terminal disconnected for about 10 minutes. Shouldn't the computer reset and clear all the codes? Did I do something wrong? Thanks for any help.
Edited by Nbe1210, 06 October 2012 - 03:01 PM.
#17
Posted 06 October 2012 - 06:12 PM
The car will run a little wonky while the computer relearns.
It will take a few driving cycles for all of the systems to become ready but hopefully that will be the end of your 0420 light show.
#18
Posted 13 October 2012 - 11:42 AM
I also just replaced the front o2 sensor with a new Bosch sensor I found on amazon fo $50. The sensor that came out of the car was a bosch so i stuck with that brand. I was able get at it through the open hood and did not have to lift the car. This one was tougher to get out. I ended up running the car for 2-3 minutes to heat it up and it came loose. The whole job took all of 25 minutes. Hopefully the car will be happy and continue to go for years. Thanks to all for the help with this little job. I'm learning new stuff all the time.
#19
Posted 13 October 2012 - 12:42 PM
MaxiScan MS300 OBD2/OBDII Car Auto Diagnostic Code Reader Scanner Tool CAN$22 shipped on ebay.
Pretty basic but it: Reads and erases codes.
Tells you if systems are "ready" if you are trying to sneak by emissions testing.
#20
Posted 13 October 2012 - 02:53 PM
#21
Posted 13 October 2012 - 03:10 PM
#22
Posted 13 October 2012 - 05:03 PM
#23
Posted 13 October 2012 - 10:51 PM
Yet another reason I use the eBay L shaped sensor spacers - they accommodate all sensors and are more effective both in fitment and in not requiring a second non-fouler as occasionally a single one isn't enough. $8 for two non-foulers that I have to drill out and mess with and fit poorly or $16 free shipping for the right part.... You do the math.
GD
#24
Posted 13 October 2012 - 11:47 PM
#25
Posted 14 October 2012 - 08:27 AM
I think it would be worth a good look at your sensor locations before ordering. I replaced the front with a new Bosch sensor but I don't think a non fouler would have fit in that space so the L would have to be the right fitting there. I don't know if it would do anything on the front sensor though.
Also, the non fouler I used must have been aluminum because it drilled like butter. Took all of a minute.
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