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Further on possible failing O2 sensor

  • Thread starter Thread starter sliepnir16
  • Start date Start date Jun 5, 2006
S

sliepnir16

New Member
May 13, 2006
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Jun 5, 2006
#1
  • Jun 5, 2006
  • #1
Earlier I made a post on the code 42, which indicates right side rich from the HEGO, and the code was from the KOER test. Today the car started acting up again so I pulled the KOEO codes first when I got home and the computer Memory read, 41,96,41,96. I know that code 41 is right side lean, so does this mean the O2 sensor on that side is definately bad? I was also working on the code 96, the regulator is new along with the relay and no matter what every time I clear the codes and take it for a drive the code always reoccurs. The car bogs out severely but eventually comes through. Could an 02 sensor have such severe symptoms or should I look more at the fuel pump?
Thanks.
 
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Daggar

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Jul 19, 2004
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Jun 5, 2006
#2
  • Jun 5, 2006
  • #2
Man... that a difficult question to answer without knowing what your AFR actually is. The code you're getting for the 02 sensor could very well be the result of an actual rich condition caused by your other problem.

If you have one or more cylinder banks that are exessively rich or lean then you will get a code for that 02 sensor any time the condition is severe enough to prevent the sensor from switching.

My suggestion would be to find and fix the problem associated with your bogging issue before running out and spending money on a new sensor.

A cylinder balance may also be in order for you. A clogged or dirty injector can severely impact the atomization characteristics and cause a rich condition. An injector stuck open call also cause this.

What is the exact verbage for the regulator code that you got?
 
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sliepnir16

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Jun 5, 2006
#3
  • Jun 5, 2006
  • #3
There is no actual code for the regulator, I thought it was giving excess pressure or something so I replaced it. I just did the KOER test and got 44,94,44,94 which have something to do with the thermactors and I have no idea about those. I did a cylinder balance and a compression test and they are all ok. I suppose the thermactors (air injection systems) could cause a rich condition but I think it should be on both sides since they are both reported inoperative. I am also considering that the fuel pump could be cutting in and out as the driving problems seem like fuel pump symptoms and its throwing the code 96 in computer memory every time I clear the computer and drive it. As far as Im concerned the AFR SHOULD be stock since it's all stock except for exhaust and a computer chip. Id appreciate any help Im at loss here.
 
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Daggar

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Jul 19, 2004
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  • Jun 5, 2006
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You need to find the source of your fuel problem. The thermactors aren't going to give you the code for the sensor that you're seeing.

I recently spent some time troubleshooting the thermactor junk on my 86. Have you ohmed out the thermactor coils yet?
 
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sliepnir16

New Member
May 13, 2006
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Jun 5, 2006
#5
  • Jun 5, 2006
  • #5
I sure haven't. On the vaccum diagram it shows the thermactor runs to the smog pump, and I don't have any smog equipment other than the EGR, I wonder if these being gone could cause that but I have not always gotten these codes.... This sucks.
 
D

Daggar

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Jul 19, 2004
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#6
  • Jun 5, 2006
  • #6
So long as you've got all the holes plugged up for your thermactor, then it's good. It's not causing your problem. If you've got an opening somewhere that's sucking unmetered air into the intake or heads that most definitely is something that needs to be fixed.
 
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