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Code 41/91 help????

  • Thread starter Thread starter Strike One
  • Start date Start date Mar 2, 2004

Strike One

Founding Member
Aug 22, 2000
715
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0
San Francisco, CA
Mar 2, 2004
#1
  • Mar 2, 2004
  • #1
The check engine light came on tonight when coming home and then went off after about 1 min. So I got home and checked for codes and I got 41/91 in the continuous memory. I looked up the code and it is "HEGO (HO2S) sensor signal out of range/always lean". Can someone explain what this sensor is? Does it mean I have bad O2 sensors?
 
D

D347643

Banned
Jan 28, 2003
1,095
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0
portland, OR
Mar 2, 2004
#2
  • Mar 2, 2004
  • #2
isnt it referring to the o2 sensors being too lean? maybe they are damaged. o2 sensors give a 0-1 volt signal reading which forms a wave pattern going 1volt then down to 0 in a matter of milliseconds. If for some reason it stays up at 1 volt for longer than normal the comp will ""think"" the car is running too rich and will decrease fuel which in turn will make your car run too lean. haha maybe im wrong about all this but that is my guess.

good luck,

Drew
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Mar 2, 2004
#3
  • Mar 2, 2004
  • #3
Ya those are o2's.. replace them, or try cleaning them if your strapped for cash.
 
D

D347643

Banned
Jan 28, 2003
1,095
0
0
portland, OR
Mar 2, 2004
#4
  • Mar 2, 2004
  • #4
woo hoo i actually got it right!
 

Strike One

Founding Member
Aug 22, 2000
715
0
0
San Francisco, CA
Mar 3, 2004
#5
  • Mar 3, 2004
  • #5
Alright, thanks guys. I will switch them out soon and hopefully it works.
 
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