Rev writes:
You know that one of the two sensors is bad.  You can spend hours
tracking down the error code to determine which one of the two is bad.
Or you can replace one.  If it doesn't fix it, put the old one back in
and replace the other one.

Or, since you're probably 100k miles past the reasonable service life
of a thin platinum wire that lives in the exhaust stream, you can just
replace both and move on to something more interesting.

-rev  <~~~parts changer who's time is worth more than a $25 sensor

Ninebal310 responds with:

First, let me apologize if I offended you.

Second, since I am not sure either sensor is bad (since the diagnostic
readout says it is the post-cat sensor, and I don't have a post-cat
sensor) I don't want to replace or waste my time replacing one or both.

Third, the motor only has 38k miles. I bought it new, so I know that is
true.

Fourth, the sensor that the diagnostics says is bad costs $139.00 not
$25.00.

Fifth, this is a learning experience for me.

Sixth, Thanks for your response.

Hank <~~has more time than money and loves to learn

Tbone writes:
If you say so but that really doesn't make sense.  The error code you
are
getting indicates a post converter sensor so your vehicle thinks it is
or
was there.  Bank 2 IIRC refers to the passenger side and sensor 2
refers to
the downstream sensor or post converter.  Without a sensor behind or
attached to the converter, how does the PCM know if the converter is
functioning properly?  Where did you get this cat-back dual exhaust?
If you
disconnect either sensor, you will get additional diag codes.  You
could try
replacing the passenger side sensor but I doubt that it will correct
the
problem.  When did the light come on in relation to your installation
of
your dual exhaust?  I would also take another look at that converter
for
that sensor.

--
I agree that it doesn't make sense. I had the Cat-back exhaust put on
about a year ago. The light didn't come on until the last month. The
truck only has 38K miles on it. I installed new Bosch Platinum plugs
also. But that was AFTER the light came on.

I have the 4.7 V-8. 2001 Dakota SLT. Is there a web site or anybody
that can tell me that it definately came with a post cat. sensor? If it
did, why so long for the light to come on? I am soooooooo confused.

I will crawl under it again and check for any wiring, plugs or sensor.
I have made mistakes in the past, just not many.....LOL.

Thanks

Hank <~~~easily confused