O2 codes from long tube headers
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
O2 codes from long tube headers
I have read all the threads on the subject and got some helpeful information. I am getting codes:
P0 135
140
155
160
I know they represent the O2 sensors the two front and two aft of the cats.
Now I don't have cats and have pluged the rear sensor bungs. I thought my tuner tuned out the rear sensors or so he said. But I am still getting all the above codes.
Now what I have learned is the positon of the sensor farther back than stock will cause problems because they don't get warm enough. I did what was recomended and bought rear senosrs and installed them in the front location and used adapters to connect them.
I have read on this forum there is some adjustment a tuner can make to the 'tables" and have the sensors work at a lower temp or come on sooner or something like that.
So that is my question what do I ask my tuner to do to make the front senosrs work?
Thanks,
Jay B
P0 135
140
155
160
I know they represent the O2 sensors the two front and two aft of the cats.
Now I don't have cats and have pluged the rear sensor bungs. I thought my tuner tuned out the rear sensors or so he said. But I am still getting all the above codes.
Now what I have learned is the positon of the sensor farther back than stock will cause problems because they don't get warm enough. I did what was recomended and bought rear senosrs and installed them in the front location and used adapters to connect them.
I have read on this forum there is some adjustment a tuner can make to the 'tables" and have the sensors work at a lower temp or come on sooner or something like that.
So that is my question what do I ask my tuner to do to make the front senosrs work?
Thanks,
Jay B
Last edited by jaybar; Mar 17, 2010 at 08:29 PM. Reason: grammer
Tech Contributor
Joined: Jan 2007
Posts: 19,398
Likes: 1,139
From: Dyer, IN
I have read all the threads on the subject and got some helpeful information. I am getting codes:
P0 135
140
155
160
I know they represent the O2 sensors the two front and two aft of the cats.
Now I don't have cats and have pluged the rear sensor bungs. I thought my tuner tuned out the rear sensors or so he said. But I am still getting all the above codes.
Now what I have learned is the positon of the sensor farther back than stock will cause problems because they don't get warm enough. I did was was recomended and bought rear senosrs and installed them in the front location and used adapters to connect them.
I have read on this forum there is some adjustment a tuner can make to the 'tables" and have the sensors work at a lower temp or come on sooner or something like that.
So that is my question what do I ask my tuner to do to make the front senosrs work?
Thanks,
Jay B
P0 135
140
155
160
I know they represent the O2 sensors the two front and two aft of the cats.
Now I don't have cats and have pluged the rear sensor bungs. I thought my tuner tuned out the rear sensors or so he said. But I am still getting all the above codes.
Now what I have learned is the positon of the sensor farther back than stock will cause problems because they don't get warm enough. I did was was recomended and bought rear senosrs and installed them in the front location and used adapters to connect them.
I have read on this forum there is some adjustment a tuner can make to the 'tables" and have the sensors work at a lower temp or come on sooner or something like that.
So that is my question what do I ask my tuner to do to make the front senosrs work?
Thanks,
Jay B
Safety Car
Joined: Nov 2002
Posts: 4,394
Likes: 6
From: Melbourne FL
I've gotten a "slow response" code from time to time because the sensors are located further back. I don't know specifically what tables need to be modified to fix this but I turned that code off completely to resolve the issue. I would think you would want to program the sensor to come on Later to prevent the code allowing them more time to heat up. I have found over the years of owning this car that my sensors seem to last ~2 years with my current mods; then they need to be replaced because the response times tend to slow, causing problems.
Le Mans Master
Joined: Nov 2003
Posts: 8,003
Likes: 249
From: Tampa Fl
St. Jude Donor '12-'13-'14
Its kind of weird with LT headers and codes. I drove around for a year with all the bolt ons (with cats but high flow) and never got a code.
Had you posted this two weeks ago, I could have clicked off the codes for you because I was at my parents house in Stuart.
Had you posted this two weeks ago, I could have clicked off the codes for you because I was at my parents house in Stuart.
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Timing is everything! How would you have clicked them off?
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Ok, HP tuners is cool. I thought you were just saying you would clear my codes. That would last about 5 minutes till the codes come back.
So am I correct in understanding that some how( with HP tuners) the o2 sensors can be "curved" to live in the cooler environment the long tube headers provide?
I did see a post during my search where a forum member drilled holes in the tip of sensor to let in more gas, I will try anything at this point.
So am I correct in understanding that some how( with HP tuners) the o2 sensors can be "curved" to live in the cooler environment the long tube headers provide?
I did see a post during my search where a forum member drilled holes in the tip of sensor to let in more gas, I will try anything at this point.
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Le Mans Master
Joined: Nov 2003
Posts: 8,003
Likes: 249
From: Tampa Fl
St. Jude Donor '12-'13-'14
Ok, HP tuners is cool. I thought you were just saying you would clear my codes. That would last about 5 minutes till the codes come back.
So am I correct in understanding that some how( with HP tuners) the o2 sensors can be "curved" to live in the cooler environment the long tube headers provide?
your front ones shouldnt have an issue, and the rears are turned off
I did see a post during my search where a forum member drilled holes in the tip of sensor to let in more gas, I will try anything at this point.
never heard of this
So am I correct in understanding that some how( with HP tuners) the o2 sensors can be "curved" to live in the cooler environment the long tube headers provide?
your front ones shouldnt have an issue, and the rears are turned off
I did see a post during my search where a forum member drilled holes in the tip of sensor to let in more gas, I will try anything at this point.
never heard of this
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
The rear o2 are removed and pluged, so those codes are meaningless, my tuner should have turned them off. But the front ones are the problem. When they "code" the car goes into open loop and runs off of the fuel curves that GM put in as the default not the custom curves my tuner installed. You can feel the difference on a road course when it changes over.
I also found on LS1 tech that the slots in the o2 sesors can be enlarged with a small screw driver by prying the slots open wider. The poster said that helped.
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Well, I checked the fuse again and it was blown. I answered eariler that it was ok but then again I had checked it a few months ago. So repalced the fuse still same 4 codes. Jacked it up looked around wires were not touching the headers everything looked good but did notice the ground strap from the frame to the engine on the drivers side was loose about two to three turns. I thighten it up let it run on the jacks and kept checking no codes. Took it off the jacks and went for a ride. Ran great got home and checked and got Po140 and 160. Meaning "slow respose" the 135 and 155 did not show up. So I am thinking it is caused by the sensors not getting hot enough but that is a guess. Is there a way to check the sensors like putting an ohm meter on some termanals etc???
I am running Demso sensors if that means anything. I put them in new with the headers.
Ideas??
One other question. Does the computer go into open loop only when the check engine light comes on? In other words am I still in closed loop even those I get the "slow response "codes?
I am running Demso sensors if that means anything. I put them in new with the headers.
Ideas??
One other question. Does the computer go into open loop only when the check engine light comes on? In other words am I still in closed loop even those I get the "slow response "codes?
Last edited by jaybar; Mar 20, 2010 at 04:32 PM. Reason: more questions
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Thank you very much. I looked at these codes so often I forgot that sensor 2 is the rear. So since they have been removed, everything is cool, I just get them programed out. Wow what a relief. Now I can enjoy my new LS-6 engine which was just installed.
Tech Contributor
Joined: Jan 2007
Posts: 19,398
Likes: 1,139
From: Dyer, IN
Tech Contributor
Joined: Jan 2007
Posts: 19,398
Likes: 1,139
From: Dyer, IN
Well, that's pretty important. That ground point is G105. It has two terminals: one being the ground strap, and one being a ground point for SP122. SP122 is the ground location for the O2 sensor(s) heater circuits, and provides a ground for the fuel pump relay, and oil level sensor.
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Wasn't sure that there were two wires on the bolt so I jacked it back up
let it cool down and went under. The bolt has two leads one the ground strap the other the lead going to the wire harness for the O2 sensors.
I had assumed both leads were connected since the o2 sensors started working after I tightened the bolt, but I had to make sure. And I guess the loose connection could have caused the fuse to blow also.
Many thanks to all who offered suggustions. This forum is the greatest!!
I don't know how many of us with limited knowledge of our cars could
get along without Corvetteforum.com
let it cool down and went under. The bolt has two leads one the ground strap the other the lead going to the wire harness for the O2 sensors.
I had assumed both leads were connected since the o2 sensors started working after I tightened the bolt, but I had to make sure. And I guess the loose connection could have caused the fuse to blow also.
Many thanks to all who offered suggustions. This forum is the greatest!!
I don't know how many of us with limited knowledge of our cars could
get along without Corvetteforum.com
