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Need help fast ** easy problem **

  • Thread starter Thread starter kosmos
  • Start date Start date Jun 7, 2009

kosmos

New Member
Dec 15, 2008
35
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0
Jun 7, 2009
#1
  • Jun 7, 2009
  • #1
Ok i have a o/r x pipe, I have the mil eliminators that have worked for 2 years no problems, but today my CEL came on, so I ran the code and it came back saying word for word.


Catalyst Efficiency Low-bank 2,

well we all know I dont have no cats, so im wondering is the actual o2 sensor bad or the mil eliminator??

what do i need to do and always which 02 is it talking about since theirs 4 total 2 in the front and 2 in the rear
 

AdRock

Member
Nov 13, 2003
521
1
19
South Texas
Jun 7, 2009
#2
  • Jun 7, 2009
  • #2
Disconnect the MIL eliminators. Clean all the connections with contact cleaner. Then put some dielectric grease in the connectors and put it back together. Reset the ECU and see if the code comes back.
 

kosmos

New Member
Dec 15, 2008
35
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0
Jun 7, 2009
#3
  • Jun 7, 2009
  • #3
Im trying to see if I can find someone who has a tuner so I can just turn the rear o2 off, do you guys think that would be easier than possibly having to buy a new set of mil's? because it doesnt sound like my o2 sensor is bad because it obviously read something was wrong, so it has to be the mil's
 

MaxedGT

Member
Mar 31, 2005
304
0
17
Surrey BC Canada
Jun 7, 2009
#4
  • Jun 7, 2009
  • #4
I've found with the mils, that everytime I reset the computer, cat efficiency codes would set after a few days of driving. But if I didn't clear the codes, the light would go out and wouldn't set again. If I cleared the codes, they would set again. So don't panik.
 

kosmos

New Member
Dec 15, 2008
35
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0
Jun 7, 2009
#5
  • Jun 7, 2009
  • #5
Ok well I disconnected the negative battery terminal for 30 minutes and check engine light is off now, but it will come back on after a week of driving, that im absolutely sure of,

so you saying that if i just leave the light on it will eventually go out?!

my first thought was maybe the mil's are dirty or loose and need to be cleaned but i dont have my jack with me at the moment.

and you cant buy mil's no more if mine have gone bad, so im trying to get ahold of my installer to see if he has a tuner that i can use to completely turn off the rear o2's but if im gathering what your saying i'll just leave the light on for awhile and see what happens
 

kosmos

New Member
Dec 15, 2008
35
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0
Jun 7, 2009
#6
  • Jun 7, 2009
  • #6
I noticed that they dont sale mil anymore?! well i cant get under the car at the moment but i do know that the plug in type MIL'S are sealed once plugged in so i dont know how dirty could get in their, also I cant find anybody that has a tuner that will turn off o2 sensors, all the new ones wont let you do it.......... so this is really starting to piss me off lol


I dont want to take the bulb out so lets say my mil has gone bad from years of use well what the hell do you do?!
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
28
119
Motor City
Jun 8, 2009
#7
  • Jun 8, 2009
  • #7
Simple....you have an exhaust leak. I had this could before on a Grand Prix. I got this could months after I changed the converter. Come to find out, the bolts at the manifold loosened up and caused the upper O2 sensor reading to be way off.
 

96SCstang

New Member
Jul 22, 2006
228
0
0
novi, MI
Jun 8, 2009
#8
  • Jun 8, 2009
  • #8
ok....first off that code is for the drivers side rear o2 sensor. bank one is always the side with the number one cylinder and on our cars that is the passenger side. that code is set on a stock car when the rear o2 reads rich for too long. this means that the cat is not effectivly burning the raw fuel from the engine. now on your catless setup it is way differnent. the mil is just a devise to fool the computer into thinking that the cat is still there. so it could be either a bad mil or a bad o2 sensor like you already said. now if you can get someone to turn off the rear o2's then do it. they are not serving any purpose whatsoever right now. otherwise you will have to figure out which part is bad.
 

squeak93

15 Year Member
Jun 2, 2005
2,253
358
164
Joplin, Missouri
Jun 8, 2009
#9
  • Jun 8, 2009
  • #9
SVT32VDOHC said:
Simple....you have an exhaust leak. I had this could before on a Grand Prix. I got this could months after I changed the converter. Come to find out, the bolts at the manifold loosened up and caused the upper O2 sensor reading to be way off.
Click to expand...


That would be true if it were sensor one but since it is for catalyt (sensor 2) then it should just be a bad mil/sensor.
 

kosmos

New Member
Dec 15, 2008
35
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0
Jun 8, 2009
#10
  • Jun 8, 2009
  • #10
I figured since the o2 sensor did pick up a problem that its obviously working fine so my thoughts go to a bad mil eliminator, so i ordered a brand new set today if it comes back its gotta be a bad 02 sensor problem solved
 

AdRock

Member
Nov 13, 2003
521
1
19
South Texas
Jun 8, 2009
#11
  • Jun 8, 2009
  • #11
kosmos said:
I figured since the o2 sensor did pick up a problem that its obviously working fine so my thoughts go to a bad mil eliminator, so i ordered a brand new set today if it comes back its gotta be a bad 02 sensor problem solved
Click to expand...

Did you even try cleaning out the connectors?

Also, you said earlier in the thread that you would try to find someone with a tuner to turn them off for you. I know you're not doing that now, but someone couldn't just turn them off for you with their tuner. You would have to buy a tuner yourself or have a shop put a chip in and turn them off in a tune.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Jun 8, 2009
#12
  • Jun 8, 2009
  • #12
swap the connectors side to side and see if it pulls a code for bank 2.
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
28
119
Motor City
Jun 9, 2009
#13
  • Jun 9, 2009
  • #13
squeak93 said:
That would be true if it were sensor one but since it is for catalyt (sensor 2) then it should just be a bad mil/sensor.
Click to expand...

But it doesn't have to be a bad sensor/mil. Could be a leak that is making the snesor throw a could. If you have a leak, fix that first.

Always do free stuff first, then spend money.
 

squeak93

15 Year Member
Jun 2, 2005
2,253
358
164
Joplin, Missouri
Jun 9, 2009
#14
  • Jun 9, 2009
  • #14
SVT32VDOHC said:
But it doesn't have to be a bad sensor/mil. Could be a leak that is making the snesor throw a could. If you have a leak, fix that first.

Always do free stuff first, then spend money.
Click to expand...


Agreed on the free fix's. But unless he has a hole in the pipe or a crack it would throw the front sensors first(there are no joints to leak after the front and before the rear sensor). The fronts are the most sensitive and will pu the extra air first. I had bad maf and it threw my front sensors and the normal "cats not working" rear code.


I say the sensor or mil has gone bad.


+1 on swaping sensor sides to see if it does the same thing.
 
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