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Discussion Starter #1
Ok guys i have the cp-e headers and ive been fine without any cels for like 5k miles.. well while driving on the highway i recieved a p0421 and a p0431 which are .

P0421 Warm-up catalyst system (RH) efficiency below threshold ON 2 Catalyst ´ (DTC P0421, P0431)

P0431 Warm-up catalyst system (LH) efficiency below threshold ON 2 Catalyst ´ (DTC P0421, P0431)

which im assuming are the actual header o2s where the pre cats used to be. Now what i need help on is does anyone on here have a diagram of where each o2 sensor is supposed to plug into? i didnt do the installation myself i had a shop do it and i just want to make sure each o2 sensor is plugged into the correct spot. Any help would be greatly appreciated. Thanks.

-Rob
 

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I would like to know it as well...I have a cel and it shows P0102 (MAF low input ON/ CCM) and P0158 (HO2 sensor LR circuit high input ON /CCM)...I have no idea what those are...most people mentioned that it might be the O2 sensor...I've checked the wires on MAF, they all look fine...however, if someone willing to help me troubleshoot the problems, I'm willing to drive (only if your in SoCal)...
 

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You probably did this already but...

P0102
http://www.obd-codes.com/trouble_codes/gen...t-low-input.php

What does that mean?

Basically this means that there is a problem with the Mass Air Flow (MAF) sensor or circuit. A more technical description would be that the MAF circuit had lower than expected voltage (air flow).
[/quote]

Sounds like the maf has issues which may be throwing fuel/air ratios downstream? Maybe try cleaning out the maf sensor as instructed on 6tech.


P0421
What does that mean?

Basically this means that the oxygen sensor downstream of the catalytic converter on bank 1 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.
Do you have the original magnaflow cats or the replaced one?
 

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Discussion Starter #4
p0421 and p0431 are the pre cat o2 sensors before the cats.. im just wondering if someone has a diagram or something or maybe if they can look at their current setup and tell me which o2 sensor plugs into what harness just so i can make sure all mine are plugged in correctly.
 

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p0421 and p0431 are the pre cat o2 sensors before the cats.. im just wondering if someone has a diagram or something or maybe if they can look at their current setup and tell me which o2 sensor plugs into what harness just so i can make sure all mine are plugged in correctly.
[/b]
i really doubt they are the pre-cats O2s. the error is saying the cat isn't operating effectively. the one's post cat measure efficiency and compare it to pre-cat o2s... basically the one's after the race cats are the sensors reporting downstream o2 levels.

if they were plugged incorrectly you would have seen this problem almost right away. my guess is an exhaust leak or the wires to the o2 sensors have somehow come loose. its unlikely that both cats would go at the same time.

let me know what the problem boils down to, cause that's where my money's at.


http://www.obd-codes.com/trouble_codes/gen...hold-bank-2.php
A code P0431 may mean that one or more of the following has happened:

* The catalytic converter is no longer functioning properly
* An oxygen sensor is not reading (functioning) properly
* There is an exhaust leak

Next step is to measure the voltage at the oxygen sensor on Bank 1 (the rear sensor, or the sensor after the converter). The voltage should be low and steady (~200mV, depends on the vehicle). If the voltage varies (e.g. 100mV to 600mV) then it's time to replace the catalytic converter. In fact, it would be a good idea to test each oxygen O2 sensor while you're at it.
[/b]
Notice, it says the "rear" sensor after the converter... not the 'pre-converter' sensors. So I would suspect the o2 sensors going to your Y-Pipe afer the cats.
http://www.obd-codes.com/trouble_codes/gen...hold-bank-1.php
 

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Discussion Starter #6
bro i looked it up online.. warm-up catalyst system are the pre cats :\ according to like 5 diff sites heh. anyone else have any info to add?
i appreciate and all help tho. first things first does anyone have a diagram or something that shows which o2 sensors connect to which harness? or can someone look on their v6 for me and let me know?
 

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Discussion Starter #8
alrite. Ill figure it out thx for the help guys.
 

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Front sensor location (White on the left side, Black on the right side):


Front sensor connections:


Rear sensor location (Green):


Rear sensor connection:


Can't get a good pic of the last sensor, but you should be able to figure it out since you know where the other 3 go.
 

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Discussion Starter #10
slv6s do you have aim or something we can talk on? i have a couple questions on the pics and it would just be much quicker to talk on aim or msn.
 

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Discussion Starter #11
The way i have it setup now is in the 2nd pic. here the gray harness with the blue connector on it i have goes into 1 of the sensors on the y pipe.

http://i98.photobucket.com/albums/l270/slv...tt/IMG_0235.jpg


now the green connector im assuming that plugs into the header facing the driver.. i need to check if i have that plugged into the correct place.. im just a little confused ill check it out and post the updates..


edit: the thing is the green connector i see plugged in their... its not green on my car its black.. what the shop did was use one of the short extensions and they plugged it in to a black connector.. IF i plug it the same way you have it i would have a black connector plugging into a gray connector which doesnt seem right which is why im confused...
 

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Discussion Starter #12
now if i go by what aj said i have everything plugged into the right spot.. the front header i have a black wire plugging into a black harness thats rite their in the engine bay uh... you cant see it in your photos ill get a pic of it.

on this photo http://i98.photobucket.com/albums/l270/slv...tt/IMG_0235.jpg
the gray harness with the blue clip on it is leading to the o2 sensor on the y pipe.

i dont even know anymore im completely confused.
 

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Discussion Starter #13
Alright guys sorry about all the random posting lol ive determined with the help of one of my friends that the shop completely screwed up my o2 sensors so now what im going to have to do is try and get all new o2 sensors from someone who wrecked their 6 possibly and then wait on the actual extensions from cp-e so i dont have to splice or anything like that. you know the o2 sensor thats wrapped in green. on mine its not green its black with a black harness so they must of switched o2 sensors which isnt good and its all screwed up. I appreciate all the help u guys have given me so far.

IF anyone knows of anyone that could sell me all their o2 sensors that would be awesome lol.
 

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slv6s do you have aim or something we can talk on? i have a couple questions on the pics and it would just be much quicker to talk on aim or msn.
[/b]
Hey man. Sorry I did get back to you sooner, but I was away all afternoon. Left right after I snapped those pics. It sounds like you figured things out though, but if you still need anything, don't hesitate to ask.
 

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Discussion Starter #16
How'd they screw it up?
[/b]
they switched o2 sensors around. Because u know how you see the o2 sensor thats wrapped in green that has a gray harness connected to it. yeah mines not green its black and its a black harness so its plugged into a completely diff spot so that means they switched o2 sensors around so i dont even know which was the green one at this point and where it goes. I spoke to josh and we are gonna work it out.
 

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Ok guys i have the cp-e headers and ive been fine without any cels for like 5k miles.. well while driving on the highway i recieved a p0421 and a p0431 which are .

P0421 Warm-up catalyst system (RH) efficiency below threshold ON 2 Catalyst ´ (DTC P0421, P0431)

P0431 Warm-up catalyst system (LH) efficiency below threshold ON 2 Catalyst ´ (DTC P0421, P0431)

which im assuming are the actual header o2s where the pre cats used to be. Now what i need help on is does anyone on here have a diagram of where each o2 sensor is supposed to plug into? i didnt do the installation myself i had a shop do it and i just want to make sure each o2 sensor is plugged into the correct spot. Any help would be greatly appreciated. Thanks.

-Rob
[/b]
yup I have been getting the same codes also, and sqanerd has been having the same problems with this o2 too.
 

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Discussion Starter #18
and you had your cats changed out by kooks rite?
 

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bro i looked it up online.. warm-up catalyst system are the pre cats :\ according to like 5 diff sites heh. anyone else have any info to add?
i appreciate and all help tho. first things first does anyone have a diagram or something that shows which o2 sensors connect to which harness? or can someone look on their v6 for me and let me know?
[/b]

and i think we're saying the same thing, it is the pre-cats... but what i'm saying is that with the headers you don't have pre-cats anymore.. you just have 2 race cats. those o2 sensors behind the race cats are now taking the place of the pre-cats.

if they did hooked it backwards , the o2 sensors would be reading raw un-catalyzed air which would totally fit in line with what you're seeing... cat inefficiency. cause the sensor is reading air before the race cats. so yeah, i think we're saying the same things.

i believe sqanerd has all his issues resolved. turns out his shop messed up the o2 sensors as well. pm him, alhtough, he may have gotten rid of his headers cause last i read he wasn't too pleased with them.
 

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Discussion Starter #20
yeah these days you cant trust many people to do shit for u cuz they fuck it up.
 
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