what do these codes mean?
Thread Starter
Racer
Joined: Oct 2004
Posts: 300
Likes: 0
From: miami florida
what do these codes mean?
i installed my lg pro long tube headers about two weeks ago. i got the car tuned and after about 200 miles i get the check engine light on. the display tells me the following codes:
po134
po154
po420hc
what do they mean? how do i correct them? is it something that can be fixed through tuning?
po134
po154
po420hc
what do they mean? how do i correct them? is it something that can be fixed through tuning?
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
134/154 are left front o2 faults,420 is a left bank cat fault.are the o2 faults current,look for a loose front o2 sensor,loose connections around the cats,anything that would cool off the o2's.may just be a bad o2 sensor.are you using rear o2's,simms,?
Intermediate
Joined: Dec 2005
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From: Cary NC
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
so i'm assuming you are running just the front 2 o2 sensors,the rears are edited out.sounds like you need to go back and see your tuner.
did you move the original o2 sensors up to the front and use the adapter pugs that came with the headers?if so,you probably have a dead left front o2 sensor[bank 1],unless it is loose.if you have no cats and simms,your tuner should have deleted them.
are you running 4 o2 sensors,if so,that is another ball of wax?
also,my fault.your faults are for BOTH front o2 sensors for insufficent activity,420 being the twc fault.
did you move the original o2 sensors up to the front and use the adapter pugs that came with the headers?if so,you probably have a dead left front o2 sensor[bank 1],unless it is loose.if you have no cats and simms,your tuner should have deleted them.
are you running 4 o2 sensors,if so,that is another ball of wax?
also,my fault.your faults are for BOTH front o2 sensors for insufficent activity,420 being the twc fault.
Last edited by dpd; Dec 28, 2005 at 01:25 PM.
Thread Starter
Racer
Joined: Oct 2004
Posts: 300
Likes: 0
From: miami florida
ok here is the deal..my tuner turned off the 2 rear sensors. yes i am using 4 02 sensors because the set up i have is off rd and i have 4 bung holes..(headers and on the off rd x pipe) so yes i had to use 4 sensors, but 2 of them are deleted.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
Originally Posted by whitecamaross
ok here is the deal..my tuner turned off the 2 rear sensors. yes i am using 4 02 sensors because the set up i have is off rd and i have 4 bung holes..(headers and on the off rd x pipe) so yes i had to use 4 sensors, but 2 of them are deleted.
if you are using 4 o2's and no cats,did you move the original rear o2's to the front and use the adapters?this is key,because the rear o2's use a higher wattage heater to keep them online[that would explain the insufficent activity faults,because they are cooling off ].
if you are not using cats or the rear o2's,you need to go see your tuner to have him redo the twc fault[ the pcm is still looking at that rear o2 sensor and comparing it to the front,if it's turned off the pcm shouldn't be looking at it]
Last edited by dpd; Dec 28, 2005 at 01:35 PM.
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Thread Starter
Racer
Joined: Oct 2004
Posts: 300
Likes: 0
From: miami florida
ok i understand that and im almost positive i did, but if that was the case and lets say i didnt do that then wouldnt my car idel all messed up anyways? my car idles perfect and i have no issues with idle and as matter of fact i have never had issues with idle even before the tune.
Drifting
Joined: Oct 2003
Posts: 1,540
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From: bloomfield nj
Originally Posted by whitecamaross
ok i understand that and im almost positive i did, but if that was the case and lets say i didnt do that then wouldnt my car idel all messed up anyways? my car idles perfect and i have no issues with idle and as matter of fact i have never had issues with idle even before the tune.
no,you are thinking about if they are crossed.if they are crossed the car will run like hell.if you used the adapters lgm sends with the headers,then you had to have moved the sensors from the rear to the front.if the car runs fine,then you have them hooked up right[left to left,right to right].the only other thing i ca think of other than 2 bad o2 sensors[front]is the fuse for the heaters is blown.if it is blown,look to see if the o2 sensor harnesses are laying on the headers.but with the rear o2's edited out you should not be setting the twc[420]fault.that's what rear o2 sensors do,monitor cat efficency,that's it.they have nothing to do with mixture.
right now you should have the original REAR o2 sensors screwed into the COLLECTORS and plugged into the ADAPTERS and plugged into the FRONT o2 female harnesses with the LEFT COLLECTOR O2 GOING TO THE LEFT FRONT O2 HARNESS AND THE RIGHT COLLECTOR GOING TO THE RIGHT FRONT O2 HARNESS.this should be right because the runs ok
Last edited by dpd; Dec 28, 2005 at 01:47 PM.
Thread Starter
Racer
Joined: Oct 2004
Posts: 300
Likes: 0
From: miami florida
im positive they probably are laying on the headers..so what you are saying is that i must have a harness laying on the headers or i have the wrong sensors connected to the front? how do i tell the difference between the front and the rear 02s? lets say i made a mistake using my fronts instead of my rears then how do i distinguish between both?
Thread Starter
Racer
Joined: Oct 2004
Posts: 300
Likes: 0
From: miami florida
ok so now u told me that i probably dont have my rear 02 sensors deleted since that code i have is usually connected to rear 02s.. now you got me all mixed up..yes, i do recall going under the car and seeing the passenger's side harness leaning on the header..i can go under the car and try to get it as far away as i can.
Drifting
Joined: Oct 2003
Posts: 1,540
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From: bloomfield nj
Originally Posted by whitecamaross
im positive they probably are laying on the headers..so what you are saying is that i must have a harness laying on the headers or i have the wrong sensors connected to the front? how do i tell the difference between the front and the rear 02s? lets say i made a mistake using my fronts instead of my rears then how do i distinguish between both?
the plugs are different between the front and rear and the harness lengths are different.the fuse for the o2 sensors is under the hood.that's why i'm asking did you use the adapter harnesses that came with the headers. the system i have only uses 2 o2's in the collectors and i use simms in the rear.my lg's are the older system,but the install is the same.if you are using 4 you should have 2 in the collectors and 2 in the x pipe.what you want is the original rear o2's up in the collectors with the adapters.
Drifting
Joined: Oct 2003
Posts: 1,540
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From: bloomfield nj
Originally Posted by whitecamaross
ok so now u told me that i probably dont have my rear 02 sensors deleted since that code i have is usually connected to rear 02s.. now you got me all mixed up..yes, i do recall going under the car and seeing the passenger's side harness leaning on the header..i can go under the car and try to get it as far away as i can.
take 10 deeps.i'm not trying to confuse you.i'm trying to figure out what you did.first-let's work on the 02 switching faults.go and check the fuse under the hood,it should be a 15amp fuse,i think it says OXY SEN,if it is blown,look to see which harness is rubbing,move it out of the way and replace the fuse.now,did you use the adapter harnesses?
Last edited by dpd; Dec 28, 2005 at 02:32 PM.
Thread Starter
Racer
Joined: Oct 2004
Posts: 300
Likes: 0
From: miami florida
i just checked it and you are right on..it is indeed blown so now i am going to climb underneath the car and zip tie the harnesses..both harnesses should be as far as possible from the headers correct?
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
Originally Posted by whitecamaross
i just checked it and you are right on..it is indeed blown so now i am going to climb underneath the car and zip tie the harnesses..both harnesses should be as far as possible from the headers correct?
ok,when you find the harness that's hitting,CHECK the harness to make sure the WIRES ARE NOT MELTED TOGETHER.if they are,that's going to be a problem.replace the fuse and we will go to the next step