Help CEL came on after putting on ractive header

mp5zoomer

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2003 mazda protege5
Ok i put the ractive header on sunday drove about 100 miles after resetting the cpu and i just got a cel after starting it up to leave work. Heres what i've
done ....i disconnected the 2nd o2 sensor altogether. I hooked the 1st o2 sensor up to a pair of spark plug foulers. then i screwed it into the header where the o2 sensor goes into(i did this after reading a thread about cel fix). i drilled a 1/2" hole in the fouler so that the o2 sensor would fit down in it. Any suggestions on how to fix this besides splitting into my actual o2 sensor wires would be great.


thanks for suggestions in advance
 
jersey_emt said:
With your 2nd O2 sensor removed from the exhaust, you will throw a CEL
so should i use the 2nd o2 sensor in the place of the 1st o2 sensor or are u saying in general that if both arn't hooked up at the same time this will happen. cause i thought this would fix the cel light coming on altogether(using the foulers)
 
ok ty i will do the soldering when i get home so after i do the mil fix on the 2nd o2 sensor do i just zip tie it inside the engine bay out of the way?
 
The 2nd O2 sensor shouldn't be near your engine bay, it should be farther downstream.

The one in your engine bay is the 1st one, which needs to be in the header.
 
mp5zoomer said:
. I hooked the 1st o2 sensor up to a pair of spark plug foulers. then i screwed it into the header where the o2 sensor goes into(i did this after reading a thread about cel fix). i drilled a 1/2" hole in the fouler so that the o2 sensor would fit down in it.
I heard about this method from a guy at work who owns a SpecV and reads thevboard.com. I think you just did it to the wrong O2 sensor. The first O2 sensor you dont do anything with. You use the spark plug foulers on the second O2 sensor farther down on the header. It is supposed to fake the sensor by limiting the amount of exhaust that gets to the sensor.

Not sure if it will work or not, worked on my friend's SpecV tho.


scorch70
 
ok i just checked and my dumbass never noticed that the factory manifold had both o2 bungs where as the ractive header only had the 1 o2 bung. so i need to have meideke or midas weld a 2nd o2 bung behind the flange (where the spring loaded bolts are). my question, is it better to weld the 2 o2 bung after the 2nd cat or just do it after the flange using the foulers. either way i have to extend my o2 wires about 12 inches or so.
 
mp5zoomer said:
ok i just checked and my dumbass never noticed that the factory manifold had both o2 bungs where as the ractive header only had the 1 o2 bung. so i need to have meideke or midas weld a 2nd o2 bung behind the flange (where the spring loaded bolts are). my question, is it better to weld the 2 o2 bung after the 2nd cat or just do it after the flange using the foulers. either way i have to extend my o2 wires about 12 inches or so.
I dont know. Im not sure either method is proven to work. You might be better off just doing the MIL fix to the second O2 sensor, and securing it up somewhere in the engine bay. The MIL fix is a known good solution, and no need to weld a new bung into the exhaust.


scorch70
 
O so if i do the mil fix using the resistor and capacitor leave the o2 plugged into the clip and just zip tie it to the side that should work for me? if so that's great news.
 
mp5zoomer said:
O so if i do the mil fix using the resistor and capacitor leave the o2 plugged into the clip and just zip tie it to the side that should work for me? if so that's great news.
As far as I know this will work. However, I havent tried it, so I cant say for sure. But you could try it, and if it doesnt work, then have the bung welded in.

Let us know if it works.


scorch70
 
I got my Ractive installed today, disconnected the 2nd O2 and threw a CEL. Get a MIL Eliminator and connect it to the 2nd O2 sensor. Being that there is no place in the Ractive header to install the 2nd O2, just connect it and zip tie it somewhere so it doesnt touch the engine and BOOM! CEL = bye byes. Oh I disconnected the negative terminal prior to installing the MIL eliminator and then reconnected it prior to start up. That will do the trick!!


Let us know....
 
Uhm, if the second O2 sensor is completely removed from the exhaust it'll give a zero or near-zero reading which will probably throw a CEL

You'll need it to give some reading, which is why it needs to be plugged into the exhaust (with either the resistor or spark plug fouler fix)
 
if you have them weld the bung behind the cat and put the 2nd o2 there -- you might not need a mil fix -- just longer wires :)
 
thanks guys ima gonna try the mil fix using the resistors and capacitor. i'l let u guys know tomorrow if it works for me or not.
 
damnit!! the mil fix didnt work after about 21-22 miles CEL came back on. granted my soldering skills suck ass.so i guess i will have them weld a o2 bung behind the cat.
 
If you already wired the MIL fix, you don't need to run beyond the cat. This will require you to extend all the wires. Just tap in at the bottom of the header and you should be fine, as long as the capacitor & resistor are the right spec and in the right spots.
 
thanks for the info but i just got a o2 bung welded on after the spring loaded bolts on my greddy catback before the first resonator. if that doesnt work then i will try the 850,000 resistor. BTW does it matter what wire i use to extend the length of the o2 to the 2nd bung.(gauge/type of wire)
 
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mp5zoomer said:
thanks for the info but i just got a o2 bung welded on after the spring loaded bolts on my greddy catback before the first resonator. if that doesnt work then i will try the 850,000 resistor. BTW does it matter what wire i use to extend the length of the o2 to the 2nd bung.(gauge/type of wire)
as long as it's equal or thicker gauge, shouldn't matter

fwiw, the 1M ohm resistor works fine for me (450+ miles no CEL)
 
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