P0430 - SES light came on after header install. Any help?

[brewman69]

Alright so I just recently installed a new header on my 08 spec-v. After about 30 miles the SES light came on. I reset the ECU, drove about another 30 miles and the SES light came back on. Its thrown DTC code P0430 which is something like "catalyst effeciency below threshhold, bank 2". Now heres the thing, ive been reading about this anti fouler trick that could work but everyone doing this trick is putting them on the 02 sensor past the actual cat converter. I do not have an 02 sensor past my cat converter. Four o2 bungs on the stock exhaust manifold, and 4 on the new header. Can this be applied to an o2 sensor that is on the header itself? I have a factory service manual for the sentra's 07-09, and it clearly stats that there is a pre cat in the stock manifold. The new header I replaced it with definately does not have a pre cat. Any ideas on what I should do?

[nametakennow]

You're going to have to figure out which sensors are the primary ones and which are the secondary ones. My guess is that there are two further down the exhaust stream and two right up by the exhaust ports. The two that are further down are the ones you want to either move or put a spark plug defouler on.

[gray07]

This is a simple fix.

the second set of o2 plugs... I the ones after the cats on the header/manifold are the ones that read to see if the cat is working properly. So if you remove the cats guess what... you are goingt o to get a CEl no matter what.

now yes there is a few ways of fixing it... You can go and get two o2 antifoulers from autozone and stack them together to space out the o2 from the hearder.. This will somewhat lean the mixture that the o2's are reading and possibly get rid of the CEl. (REMEMBER DO NOT DO THIS TO THE O2 SENSORS THAT ARE NEAR THE HEAD, THESE READ THE ACTUAL AFR'S AND IF YOU MESS WITH THEM YOU WILL KILL YOUR MOTOR!!!)

or you can fix the CEl buy making your own electronic CEl eliminator or uying one. There are a thousand websites out there that show how to do it. All 06 and up mustangs have the same second o2 sensor as the b16 sentra (yes same part number too). and you can easily just re wire it.

Here is a thread from a mazda sitehttp://www.mazda3club.com/showthread.php?t=44407

[Outkast]

I have a factory service manual for the sentra's 07-09, and it clearly stats that there is a pre cat in the stock manifold. The new header I replaced it with definately does not have a pre cat. Any ideas on what I should do?

That is your problem. Either you need to reinstall the original cat, put an aftermarket cat in between the 2 o2 sensors, or deal with the light.

[gray07]

That is your problem. Either you need to reinstall the original cat, put an aftermarket cat in between the 2 o2 sensors, or deal with the light.

This is the best bet.. but with the new b16 design the cats were built into the stock header (yes it is a header not a manifold). so you woul dhave to extend the o2 wires to a spot on the exhaust pipeing and put another cat before the o2 sensors!!! THis would run you about 500+ done right!!

so just re wire the secondary o2's with the web page.. or buy some o2 sims off of a trans-am/ camaro or mustang website...

this is not a new thing to deal with becuse domestics have been doing this for over 10 years now and know how to kill just about any SES light.

http://www.fordmuscle.com/arch...x.php

http://www.newcelica.org/forum...16641

http://www.summitracing.com/pa...10454if the plugs are the same (4 wire) than these "should jsut snap right in".. the o2's on this car are nothing more than standard narrow band boshce o2 sensors that you can get anywhere.

http://www.paladinmicro.com/Mu...r.htm

http://atomicinternet.homeip.n...dID=8

again rememebr NOT TO mess witht he first two o2's... if you do it will kill your mototr. The first two ARE WIDE BAND o2 sendors... they read the actual AFr coming from the motor and mak changes...

the second set of o'2's th ons that read if the cat is working or not... ONLY re wire these...

if you need to go to a junk yard and pull 3-4 used o2's from a mustang or other sentra (make sure they are 4 wire) and get to work on some practice

[gray07]

Ok I did some reasearch and found that the plug on the Mustang 02 sensor is differant from ours. But I loked up the size and the voltage to compare to the b16 sentra..

the volts and size are the exact same. the only differance is the style of plug.. I am going to do some resaearch to see if any other vehicle uses the same type of o2 sensor and plug

here is the page for our stock o2 sensors.

http://www.densoaftermarket.co...=o2sn
Modified by gray07 at 10:13 AM 10/28/2009

[nametakennow]

Agreed that the first two ought not be messed with, though it's doubtful it'd kill the engine. Knock sensors and so forth would cut in first, but it's the later two that are the culprit here anyway, so there's no reason to mess with the first two.

Extending the wiring of the second O2 sensors and putting them after the main cat (underneath the car roughly astride the front seats, usually) would fix your code. FL doesn't do much in the way of emissions inspections anyway, so it's doubtful you'd get flagged from a visual inspection. This would not cost $500. Probably $100-150 or so to just extend the wires and weld a couple of bungs into the catback.

The other option is, as mentioned, the spark plug defouler trick.

[brewman69]

Thanks for all the help guys. I got my antifoulers all drilled out so Im gonna try and install it today. Ill let everyone know if it helped or what not. Definately gonna try this fix first cause it costs about 4 bucks to do instead of 100. If this doesnt work I will try an o2 sim.

[brewman69]

Ok So after I took the o2 sensor out of the aftermarket header I see that it does not fit into the antifouler that I drilled out. I even used a 1/2 inch bit just like they said. Still doesnt fit. I just want to clarify that there are no o2 sensors on my car other than the ones that were on the stock exhuast manifold (or header whatever you want to call it). There are four. The top two are supposed to be air/fuel, and the bottom two are supposed to be heated oxygen sensors. Which would mean that the only oxygen sensors in my car are located downstream of the pre-cat that was in the stock manifold. Now I guess my question would be is it ok to install an o2 sim on the oxygen sensor that is in "bank 2" (cause thats the one that obviously monitors the pre-cat).

[nametakennow]

O2 sim needs to go on both the sensors that were after the precat.

If you drilled out the antifoulers more, would the sensors fit? It could be that the new sensor design is simply larger...

[08redspec]

i did the same anti fouler trick on my 08. use a half inch drill bit and just keep drilling on it til the sensor fits in. it takes a little bit but it will fit believe me. don't force it in. When you are drilling kinda move it from side to side as you drill to thin the wall down a little bit. that's what i had to do. oh and btw my light is still on. let me know if you have any luck. i think i have a bad o2

[brewman69]

Alright so I was able to drill out the antifouler a little more to make the sensor fit. Now that red is saying that his is still on my hopes arent too high that it will work. Anyway I reset my ecu and the light has been off. Drove about 20 miles today to work so ill let you know if it comes on. Last time it was around 30 miles when it came on and ill hit that mark on the way home.

[brewman69]

Oh and I only did one of the sensors in the anitfoulers. I did the one that is in bank 2 cuase that was the only code that was being thrown. If the check engine light comes on and it gives me the same code only in bank 1, that may mean it is working and that I have to install antifoulers on the other heated oxygen sensor. Ill let you know. Hopefully the light just doesnt come back on...

[gray07]

Oh and I only did one of the sensors in the anitfoulers. I did the one that is in bank 2 cuase that was the only code that was being thrown. If the check engine light comes on and it gives me the same code only in bank 1, that may mean it is working and that I have to install antifoulers on the other heated oxygen sensor. Ill let you know. Hopefully the light just doesnt come back on...

i'm telling you man.. by the time you waste your money doing the "anti-foulers and drilling and guessing you could have already re wired the o2 sensors and NEVER HAVE ANOTHER CODE AGAIN!!!!!!!!

[brewman69]

Sweet. I installed the antifoulers a couple days ago on only one sensor and guess what......no SES light!!! So far Ive driven about 80 miles and it hasnt came back on. As of now I think its fixed but I guess there is a chance it could pop back on. FOr now though, I believe its fixed. Only cost me 4 bucks too, and about 3 hours worth of work.