1997 Pontiac Sunfire O2 Sensor

1997 PONTIAC SUNFIRE
Avatar
WHYTETYGERGUY
  • MEMBER
  • 1 POST
Engine Performance problem
1997 Pontiac Sunfire 4 cyl Front Wheel Drive Automatic 160K miles
----------------------------------------------------------------
I need to replace the OS sensor on my wife's car and am not sure which one to buy. On costs $20 and one costs $70. They tell me it's a matter of whether it's before or after the catalytic converter. I can't seem to figure out which it is. What exactly am I looking for?
Mar 26, 2008 at 4:06 PM
Advertisement
Avatar
BLACKOP555
  • CERTIFIED EXPERT
  • 10,386 POSTS
that depends on what one you want to cost, the one before the converter is the one that adjusts the fuel mixture and when bad cuases engine running problems. it is known as bank 1 sensor one or bank 2 sensor one.

sensor 2 is after the cat and is just to tell if the convertor is functioning properly.
Mar 26, 2008 at 7:17 PM