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a/f gauge, bad o2's??

  • Thread starter Thread starter Emoney8924
  • Start date Start date Aug 24, 2006

Emoney8924

New Member
Sep 22, 2003
77
0
0
columbia, ct
Aug 24, 2006
#1
  • Aug 24, 2006
  • #1
hey guys, i hooked up my a/f gauge the other night, and then when i went to try it out and make sure theres good connections, i turned it on, and there was a red light at the bottom, and a yellow light in the middle of stoich.. i tried to warm up the car too.. they stayed the same, so i tried the other pin to the other sensor, same thing, could this mean failing o2 sensors?? ive over looked the connections 4 times now.. everything is fine with that..
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Aug 24, 2006
#2
  • Aug 24, 2006
  • #2
The stock NB sensors toggle between .1 and .9 volts (lean and rich, respectively) quickly. Those NB gauges are not really accurate enough to tell you very much of anything.

Now if the gauge never moves, that can tell you that there might be a dead O2 or bad harness, but I wouldnt read a whole lot more into it than that.

Good luck.
 

Emoney8924

New Member
Sep 22, 2003
77
0
0
columbia, ct
Aug 24, 2006
#3
  • Aug 24, 2006
  • #3
thanks man, so can i hook up a voltage meter onto the sensors?? if so where would i hook them up??
 

94-302-vert

Active Member
Aug 16, 2004
1,947
2
36
NE CT
Aug 24, 2006
#4
  • Aug 24, 2006
  • #4
Is the red light to indicate power?

Do you suspect your car is not running proper A/F?
 

Emoney8924

New Member
Sep 22, 2003
77
0
0
columbia, ct
Aug 24, 2006
#5
  • Aug 24, 2006
  • #5
well since its lit up, there has to be power running to it... but the a/f, im guessing its off, the thing that gets me though is that there are 2 lights on, on the gauge, the far, left (lean) and the one exactly in the middle of stoich... and they dont fluctuate, the only way the stoich light goes out is if i put the pedal like 25%-50% down then its just the red light by itself.. im guessing some bad o2's the car has like 120,000 but im not sure if they have ever been replaced
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Aug 24, 2006
#6
  • Aug 24, 2006
  • #6
You can use a meter to test the sensors. As the sensors age, they lose frequency and amplitude (dont switch as fast and dont have the range they once did).
 
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