How to cure Cel/Mil from removing cat with Non-Fouler

I got mine at Advance Auto in the "Help!" section, it came with two gaskets.

amsgator said:
did that come w/ only one gasket or two? it looks like one in this picture but in some of the others it looks like two...
 
Metallic36 said:
I got mine at Advance Auto in the "Help!" section, it came with two gaskets.

what part number? i got the 42002 and it didnt come w/ any. and it was help brand too....idk
 
I got mine from NAPA with the part number from the first few post, which I assume is the same as the above pic, and it didnt have any gaskets, but I have had no problems without them anyways so it dont really matter I dont think.
 
Got a question.. if I use an AEM Wideband, do you have to use this trick for the wideband O2 sensor? I have my exhaust with no cats.
 
I dont know about with the wideband, I guess it would make the reading differ just as it normally would?


But on another note...I got my first ever CEL tonight while driving home from shooting some pool. It just came outa nowhere and was still running fine, when I got home I couldnt find anything wrong so I just reset the ECU and sence its not running funny I should be ok, but I will have it checked if it comes back. The only think I can think of would be a 2nd O2 code anyways because of the header and non-fouler, do you think its possible to go 15k without a CEL and then suddenly get one? Possible that the non-fouler needs cleaned off? Im at a total loss here guys, it never ran funny before or after the CEL and I dont know what it could be.
 
okay read the whole thread!!.

question.

i got a hiboost turbokit. had a obdII code but forgot which one anyways. its h02s voltage too high.

and also have the p0505 IAC circuit malfuntion. cause could be ran the car too long when it was running too rich . pure black smoke coming out of the exhaust. ?? so therefore the IAC valve cloggeD? or ruined for good. havent tried cleaning it out.

so could this bung O2 non fouler fix all of that? i only have the o2 sensor that is on te exhaust pipe before the one for the midpipe hooked up . so i totally have the second one not connected not there at all

where should the second bung go to? inbetween the first o2 where the original first cat went and the midpipe? or is it afther the midpipe or
in other words behind the catylitic converter on the midpipe?

please help me. i have been told by a former porshe tech that . it would solve all my problem and will make the car run better performancewise and should be more streetable to drive.

what i get ? when first starting the car !! the idle needle flutters up and down but slowly not drastically (after car is up to operating tm p it idles fine) ,
and when i put the heater or ac on no matter what setting 1-4 needle or idle dibs down. and sometimes i swear i smell rotten egg smell. i know i could be running rich.
 
^You shouldnt run the car without both o2 sensors, thats your main problem... If your running a second cat just put the other bung on the midpipe after the cat and you wont need a non-fouler.


On another note... Ive had the non-fouler in for quite some time now and about a month ago I got a CEL, but sence I was 99% sure it was because of the header I reset it. Now, hundreds of miles later it comes back, so I stop off at auto zone and get it read. It was a 2nd O2 sensor code just as I thought so I came home and cleaned off the non-fouler and O2 sensor. Also my battery was getting some nasty corossion on it as well so I cleaned that up. Question is, do these look too dirty? They looked about normal to me...

DSC04167.jpg


I cleaned them up anyways and reinstalled them, as for my battery, it was just a 5 min job....

DSC04171.jpg


As a result of cleaning my battery terminal I have reset the code and hopefully it wont come back, because having to rest all my custom settings on my radio is becomming a pain in my ass. I have no real question here, I just wanted to update on everything, but why the heck not while im here... Can reseting the ECU too many times be stressful on the motor or the computer systems at all? Thanks:)
 
my o2 sensor isnt that dirty but the non fouler is. idk if that helps or not. coke on the corrosion works wonders! just rinse of the stickyness :)
 
amsgator said:
my o2 sensor isnt that dirty but the non fouler is. idk if that helps or not. coke on the corrosion works wonders! just rinse of the stickyness :)

Yeah, I didn't clean the O2 when I did the header install, I think I probably shoulda. Ive heard coke works well on the corrosion but I still cant bring myself to pouring coke in my engine bay. I got it cleaned up tho:)
 
jeg0024 said:
Yeah, I didn't clean the O2 when I did the header install, I think I probably shoulda. Ive heard coke works well on the corrosion but I still cant bring myself to pouring coke in my engine bay. I got it cleaned up tho:)

sweet deal. all better now?
 
I just installed my new OBX headers into my '03 MP5. I also installed the non-foulers as described in the forum. My CEL came on within 10 miles after th install. I realized that I didn't put a gasket between the two non-foulers, but I did put one between one non-fouler and the header. Before I go jack my car up again, do you think this could be because of the missing gasket? Would drilling the 1/2" hole very slightly off center make a difference? Thanks!
 
I dont have any gaskets on my non-fouler other than the one on the )2 sensor. Did you disconnect your battery durring the install to reset the ECU? Are you sure that everything else is tightened down and not leaking? Just reset the ECU again and see if the CEL comes back. And no, it shouldnt matter about the drilled hole as long as the sensor still fits into it. Just make sure you have done everything right.
 
jeg0024 said:
I dont have any gaskets on my non-fouler other than the one on the )2 sensor. Did you disconnect your battery durring the install to reset the ECU? Are you sure that everything else is tightened down and not leaking? Just reset the ECU again and see if the CEL comes back. And no, it shouldnt matter about the drilled hole as long as the sensor still fits into it. Just make sure you have done everything right.

my non foulers didnt come w/ gaskets. make sure it's not leaking, i seafoamed my engine and looked for leaks :) had to tighten the non foulers a lil more.
 
Yes, I have reset the ECU several times. I'll check for leaks tomorrow and update you on the progress. Thanks for getting back to me!
 
Ok, I just made sure that everything was on tight, and I don't see any leaks. I reset my ECU and after about 3 min the CEL came back on. I checked what the engine error was and got the following info:
P0031
HO2S Bank 1 Sen 1
Heater Circuit Low

I'm thinking I might have f'd up my o2 sensor somewhere in the mix. Any ideas?? I'm at a loss otherwise. I'd really like to get my car working as I have not been able to fully test out my new headers! Help is appreciated, thanks!
 
Ok, I took a chance and went and replaced my o2 sensor, and it worked. My car works, and I am STOKED!

Just a hint: I didn't know that you're not supposed to touch the ends of the 02 sensors. I know I touched it during my header install, and I blame that for making my o2 sensor go out. DO NOT TOUCH THE TIP OF YOUR O2 SENSOR!!!
 
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Un pregunta...

What happens when I throw all my stock stuff back on the car for CA Smog inspection and leave this contraption on there? No problem?
And what does this make te ECU do to the Air/Fuel mixture? Leaner or richer or stays the same as with both cats?
 
threw a CEL yesterday and....it was the 02 sensor.... it said

DTC (Codes)
P0140
O2 Sensor CKT No Activity
(Bank 1 Sensor 2)

DTC Pending (Codes)
No Faults Detected

so is the sensor screwed and i need a new one? the CEL didnt pop back on on the way home, so i am guessing it will take another 100 or so miles for it to come back on
 
jeg0024 said:
^You shouldnt run the car without both o2 sensors, thats your main problem... If your running a second cat just put the other bung on the midpipe after the cat and you wont need a non-fouler.


On another note... Ive had the non-fouler in for quite some time now and about a month ago I got a CEL, but sence I was 99% sure it was because of the header I reset it. Now, hundreds of miles later it comes back, so I stop off at auto zone and get it read. It was a 2nd O2 sensor code just as I thought so I came home and cleaned off the non-fouler and O2 sensor. Also my battery was getting some nasty corossion on it as well so I cleaned that up. Question is, do these look too dirty? They looked about normal to me...
computer systems at all? Thanks:)

i threw a CEL yesterday and it was the 2nd one too after like 1000 miles w/ the non fouler. what did u clean it w/? i am gonna clean mine hoping it wont come back
 
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