Re: O2 Sensors and "Smelly Cats"

[Jim Griffin <JGriff@pobox.com>]

At 02:49 AM 12/18/96 -0500, you wrote:
>>I have an '87 5KTQW and in the last few months the MPG has dropped from an
>>average of about 27.5 mpg to about 22.5 mpg. Don't seem to have and
>>performance problems - great starting and acceleration. Any thoughts???
>
>O2 sensor.....
>
>Later!
>
>Eric Fletcher S.O.C.
>'87 5KCSTQIA2RSR2B

I've been experiencing the same MPG drop for a while, and as well, a
part-throttle miss/hesitation occasionally (remember my post about spark
plug wires?). I also get that distinctive rotten egg smell sometimes,
especially at tollbooths after being on the highway at normal/high speeds
(I'm sure they love me when I pull up!!) From what I recall, a bad O2 sensor
could be causing this (over-rich condition?) as well. Or maybe I just have a
"smelly cat" (with apologies to  Phoebe on the Friends TV show!!)? 

So, do you think that my O2 sensors are bad? How can I tell? Wouldn't they
give me a diagnostic check light or something? About how long do they last,
on average? Is this a routine maintenance item, that should be replaced at a
specified time or mileage interval? I have 96k miles on my '92 V-6. Is it
about time?

If I don't get them replaced, will I continue with "smelly cat", and
eventually kill the cats as well? I've heard that an over-rich condition
will kill them for sure....

P.S. Has anyone with a V-6 changed their O2 sensors? If so, was it an easy
job, and how much did it cost? Are the sensors a dealer-only item? Any
suggestions as to best place for parts etc....?

TIA

                             Jim Griffin
                      JGriff@pobox.com
  http://www.geocities.com/MotorCity/4475
                        Maryland, USA
   "Perception is often stronger than reality!"
                               '92 100S
~~~~~~~~~~~~~~OOOO~~~~~~~~~~~~~~