Passenger side O2 sensor been unpluged for months!!
#1
Passenger side O2 sensor been unpluged for months!!
I was under the car 2 days ago.. fixing an exhaust leak... when i find that my passenger FRONT O2 sensor was unplugged?? i couldnt believe it, it must have happened when i disconnected it a long time ago and forgot to put it back on...
the strange thing is.. i never had a check engine light come on.. and the car didnt run rough.. i did notice a decrease in MPG.. by about 8mpg less than what i was used to...
but im finding it odd that it was disconnected and no check engine light ever came on... my light does work because it has come on for other things..
Should i be worried that something in the PCM is faulty?
i do have the EGR,AIR, and rear O2 deleted in the PCM.. would this make a difference at all?
the strange thing is.. i never had a check engine light come on.. and the car didnt run rough.. i did notice a decrease in MPG.. by about 8mpg less than what i was used to...
but im finding it odd that it was disconnected and no check engine light ever came on... my light does work because it has come on for other things..
Should i be worried that something in the PCM is faulty?
i do have the EGR,AIR, and rear O2 deleted in the PCM.. would this make a difference at all?
#2
TECH Addict
iTrader: (10)
Join Date: Jun 2004
Location: Commerce Twp, MI
Posts: 2,918
Likes: 0
Received 0 Likes
on
0 Posts
It's possible the tuner killed the SES light for the front O2's - especially if you have long tube headers. They tend to trip codes for insufficient activity. I don't personally agree with turning them off. All it seems to do is keep them from having to explain to someone after a tune why their SES light is on. I'd rather know so I could fix the issue given the fact that the front O2's are responsible for closed loop fueling. In your case, you were probably running in open loop. If they tuned it right, your AFR should be pretty close...so I doubt you hurt anything. But before you go plugging that O2 back in, you might want to replace it. An O2 in the exhaust without power is damaging to that sensor. And if you're going to replace one, you should really replace the other so they read the same. Just my $0.02.
Trending Topics
#8
TECH Senior Member
iTrader: (25)
You usually have 4 choices with codes.
1. MIL on 1st error.
2. MIL on 2nd error.
3. No MIL. (stores code but does not turn on MIL)
4. No Error Reported.
For the AIR, EGR, and rear O2s you set all those codes to No Error Reported. That is the just how you turn those off. What it looks like in your case is that they maybe also set your front O2s to either #3 or #4. That's not a comon practice as you need those O2s working and need to know if they are not. The only way to know for sure is to have someone read the cal out of your PCM and see what they are set to.
1. MIL on 1st error.
2. MIL on 2nd error.
3. No MIL. (stores code but does not turn on MIL)
4. No Error Reported.
For the AIR, EGR, and rear O2s you set all those codes to No Error Reported. That is the just how you turn those off. What it looks like in your case is that they maybe also set your front O2s to either #3 or #4. That's not a comon practice as you need those O2s working and need to know if they are not. The only way to know for sure is to have someone read the cal out of your PCM and see what they are set to.
#9
do you guys find it odd though.. that the car didnt stumble or run bad? I mean i did get less mpg but other than that, the thing acted normal..
i whish i knew someone with equipment to look at my PCM.. i dont know a soul in my area that has access to this..
i whish i knew someone with equipment to look at my PCM.. i dont know a soul in my area that has access to this..
#11
i live in Utah... and finding someone with HP or EFI Live is few and far between.. i have asked on the western board.. as well as other places.. so far no one has stepped forward.. and there are not too many performance shops that are astute enough to deal with LS1 PCM's.. most around here are import tuners, like COBB tuning for Subaru's.. and others for mitsubishi's..
i guess i can take her down to CA since i am orignally from there..
on a side note.. i just ordered 2 bosch 13111's, just incase the O2 was bad.. might as well replace them both..
i guess i can take her down to CA since i am orignally from there..
on a side note.. i just ordered 2 bosch 13111's, just incase the O2 was bad.. might as well replace them both..
#13
TECH Senior Member
iTrader: (25)
Originally Posted by GR33N GoblinM6
i have a different question...
if i got a hold of a scanner/code reader... would it show any codes if there were any set, if the MIL was disabled?
if i got a hold of a scanner/code reader... would it show any codes if there were any set, if the MIL was disabled?