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Installed IC and DP flashed Stage 3, now have questions

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#1
Finished up the install on my Levels intercooler and DHM downpipe this morning. Both are nice pieces with good fit and straightforward install.

The DHM downpipe only has one O2 bung. I hooked up the black O2 and left the blue off. Flashed stage 3 93oct tune. Power feels good, but I got a CEL. Don't have the AP with me so can't pull the code but imagine it's for O2. Should I plug the other O2 in and just zip tie it off? Is my CEL on bc I didn't even plug the other one in? I'll troubleshoot it tonight but wanted feedback in the meantime.

Pics


 


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#2
The check engine light is on because the rear O2 sensor needs to be shut off since it is not there on the downpipe. I have DHM downpipe as well, I have a pro tune from Randy for my 93 OCT tune and I just asked him to shut it off for me. Same with my PRO tune on E30 from Russell at DHM, Just need the rear o2 sensor shut off. I cant remember the actual code number but that is the code that is on.
 


Kip2MyLou

2000 Post Club
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#3
Finished up the install on my Levels intercooler and DHM downpipe this morning. Both are nice pieces with good fit and straightforward install.

The DHM downpipe only has one O2 bung. I hooked up the black O2 and left the blue off. Flashed stage 3 93oct tune. Power feels good, but I got a CEL. Don't have the AP with me so can't pull the code but imagine it's for O2. Should I plug the other O2 in and just zip tie it off? Is my CEL on bc I didn't even plug the other one in? I'll troubleshoot it tonight but wanted feedback in the meantime.

Pics


You went dhm dp but not intercooler :O

Just kidding.
 


OP
StayPuft
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Thread Starter #4
The check engine light is on because the rear O2 sensor needs to be shut off since it is not there on the downpipe. I have DHM downpipe as well, I have a pro tune from Randy for my 93 OCT tune and I just asked him to shut it off for me. Same with my PRO tune on E30 from Russell at DHM, Just need the rear o2 sensor shut off. I cant remember the actual code number but that is the code that is on.
I thought the code was disabled with the stage 3 ots tune. Here's a quote by rodmoe from the downpipe thread. Maybe I'm understanding it wrong.

Good Call ya got me thinking So I opened up the OTS stage 3 v103 93 oct tune in the COBB ATR and Sure enough the P0420 DTC box is Unchecked
[party]"BONUS !!"

You went dhm dp but not intercooler :O

Just kidding.
Ha! Wish I had the DHM IC but the Levels was a good price. I like buying used bc i can sell it in a couple years for same price I paid. Haven't seen a used DHM IC pop up anywhere yet and when one does it will be gone in a flash
 


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#5
[MENTION=1548]StayPuft[/MENTION] Yes the OTS Stage 3 map turns off code P0420 but that is for the downstream O2 sensor, or the front which ever you want to call it. Since it is catless that light has to be turned off. But the rear o2 sensor is believe is code P0421 or something like that, It is for the rear sensor that is not utilized on the DHM downpipe. Sorry for the confusion.
 


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#6
[MENTION=1548]StayPuft[/MENTION] Yes the OTS Stage 3 map turns off code P0420 but that is for the downstream O2 sensor, or the front which ever you want to call it. Since it is catless that light has to be turned off. But the rear o2 sensor is believe is code P0421 or something like that, It is for the rear sensor that is not utilized on the DHM downpipe. Sorry for the confusion.
 


J2FoRS

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#7
[MENTION=1548]StayPuft[/MENTION] Yes the OTS Stage 3 map turns off code P0420 but that is for the downstream O2 sensor, or the front which ever you want to call it. Since it is catless that light has to be turned off. But the rear o2 sensor is believe is code P0421 or something like that, It is for the rear sensor that is not utilized on the DHM downpipe. Sorry for the confusion.
So that being said....did he leave the wrong one out? Or your saying rodemoes explanation only refers to the catted DPs not requiring the downstream sensor in but still have the rear? Thanks for your help.
 


Sekred

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#8
I thought the blue wire sensor is the wideband 5 wire sensor that's installed before the Cat and must be used.
 


OP
StayPuft
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Thread Starter #10
So that being said....did he leave the wrong one out? Or your saying rodemoes explanation only refers to the catted DPs not requiring the downstream sensor in but still have the rear? Thanks for your help.
I understand what he's saying. It's all in the codes. P0420 is related to the o2 sensors telling each other that the cat is warmed up. And because a new downpipe generally moves the downstream/lower/blue chord O2 however you want to put it sensor further away from the upstream/upper/black chord sensor, COBB removes the slow switching code related to warmup. This is a common code for anyone installing a new DP or V8 guys installing long tube headers bc the o2s are moved so far away from each other in different temp zones.

He's saying it's probably NOT that and it has to do with the fact that I'm not running a rear o2 at all, which is probably a P0421 code.

It's impossible to mixup the o2 wires. One is like 3ft long and the other is 1' long. Then again I have been known to be completely wrong.
 


OP
StayPuft
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Thread Starter #12
I think he answered the necessity of the lower o2 and how to handle it in his DP thread.

http://www.fiestastforum.com/forum/...ck-Turbo-HiFlow-304-SS-Race-Downpipe!!!/page4
Is there only one O2 bung?
If you want I can put the 2nd one in but it is not needed with the catless set up.

Russ
I don't have a problem with no Sensor 2 and I understand it'll be tuned out, but what do people generally do with the o2 line/sensor when there's 1 bung? Does Sensor 2 just get zip tied up?
Unplug it and toss it with the rest of your stock parts you dont use! lol

Russ
I guess I just assumed wrong as far as the COBB OTS tune goes.
 


OP
StayPuft
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Thread Starter #13
Also, here's a good comparison pic taken from masonturbos build thread showing the o2s

 


OP
StayPuft
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Thread Starter #16
I like your Hyper in the background! I have a 2012 EVO 1100SP.

View attachment 6217
Very nice! Mine's a 2011. In the 3 years I've had it I still haven't seen another EVO SP on the road. Is that a full exhaust or a separate cat eliminator? Also what mirrors you running? I've only taken to the track once and it was a blast

older pic


[video=youtube;1kl8bBVvbME]https://www.youtube.com/watch?v=1kl8bBVvbME[/video]




Yes the OTS Stage 3 map turns off code P0420 but that is for the downstream O2 sensor, or the front which ever you want to call it. Since it is catless that light has to be turned off. But the rear o2 sensor is believe is code P0421 or something like that, It is for the rear sensor that is not utilized on the DHM downpipe. Sorry for the confusion.
On topic, I pulled the code and its P0141 which is basically a bad #2 sensor, as expected since it's not there! I should be fine maybe other though i think I read in some COBB forum posts that on the COBB ots tune they still use the rear o2 to an extent. Again, maybe I'm misunderstanding.
 


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#17
[MENTION=1548]StayPuft[/MENTION] Yes that is what it is. Every other DP on the market uses the Rear o2 sensor. Russell does not because it does not effect anything. I drove around for a few weeks before I got tired of seeing the light and had Randy turn it off on my 93 OCT tune. It does not mess with anything just a check engine light for no sensor lol.
 




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