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Oxygen sensor question

  • Thread starter Thread starter n2o-89fox
  • Start date Start date Dec 22, 2007
N

n2o-89fox

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Oct 8, 2007
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Dec 22, 2007
#1
  • Dec 22, 2007
  • #1
I was in the middle of replacing my o2's because they are the factory ones and I figured I should replace them. Anyways I was trying to remove them and couldnt so I broke one so I could get a socket on it and still was not able to remove it. Now with both of them unplugged and the one broken I drove the car to an exhaust shop to have them remove them and the car ran the same. No change at all in performance or idle. Shouldnt it have ran worse?? Or ran really rich?? Shouldnt the check engine light have came on? Granted I only drove it for about a mile but still shouldnt I have noticed a difference somewhere?? Oh and there is no custom tune or chip turning them off or anything.
Thanks for the replys
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Dec 22, 2007
#2
  • Dec 22, 2007
  • #2
You were probably running FMEM and foxes run pretty decent like that.

As for the CEL, you might not have driven long enough. In my experience, it can take over 10 mins of driving for the CEL to come on. They take 30 seconds to 2 mins to light off and then there's a lag-time before the computer decides the signal is never going to stabilize.
 
N

n2o-89fox

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#3
  • Dec 22, 2007
  • #3
wow good to know, thanks!
 

NIKwoaC

中國製造
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Oct 31, 2006
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Dec 22, 2007
#4
  • Dec 22, 2007
  • #4
If you only drove it for a mile, it probably stayed in open loop, and then it ignores the O2's anyway. O2's are just there to monitor AF ratio over time, and the computer slowly makes adjustments based on the signal output, so its not like your situation was going to cause a dramatic, instantaneous change in operation. Something that would cause havoc right away would be like a missing/damaged MAP sensor or TPS, etc, things that determine needed fuel supply (A/F ratio) directly.
 
N

n2o-89fox

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#5
  • Dec 22, 2007
  • #5
can I get a picture of this map sensor I dont think my car has one.
 
N

n2o-89fox

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Oct 8, 2007
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Dec 22, 2007
#6
  • Dec 22, 2007
  • #6
also where is it located I think the guy before me took it off. how would it be hooked up?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Dec 22, 2007
#7
  • Dec 22, 2007
  • #7
You don't have a MAP sensor. Mass air cars have a BAP. It would be your old MAP sensor without a vacuum line attached to it.
 
N

n2o-89fox

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Dec 23, 2007
#8
  • Dec 23, 2007
  • #8
its not there, I just noticed it should be a bap sensor but can anyone tell me where it supposed to be or a pic of where it is located? I have alot of unhook electric connectors on the passenger side and I think when the dumbass that took all the smog stuff off he took that off too. Would this cause a slight stumble once after starting the car and then it is fine after it does it once?
 

Black1987Stang

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Aug 22, 2004
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Dec 23, 2007
#9
  • Dec 23, 2007
  • #9
While we're on the subject and you got your question answered, what happens when there's only one 02 sensor signal being sent to the computer? Does it stay in open loop or limp mode? Ive been running on one 02 sensor for a while now and I get alot of weird stuff going on tunewise,. Reason I'm only running on one 02 sensor is because I took it out to put in a wideband and the narrowband simulator isn't working.
 

Black1987Stang

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Dec 23, 2007
#10
  • Dec 23, 2007
  • #10
and to answer your question the map/bap sensor should be on the firewall in the center, right above the intake, it's black and plastic with I believe a 3 wire harness going into it and held in by 2 nuts.
 
P

PJC Racing

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Nov 21, 2007
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Dec 23, 2007
#11
  • Dec 23, 2007
  • #11
As a note: its easier to remove O2's when the exhaust is hot.
 
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