... get replaced for the wrong reasons.
You need to know that OBD2 code Readers speak in code.
Even though you're reading: "aging sensor ahead of catalyst, bank 1-3" the only thing that's a given is that it's happening on the right bank of the engine.
The aging sensor doesn't mean that it's an old sensor, but rather that the signal the ECU expects to see from the sensor is weaker than it wants.
It could be that the O2 sensor is bad, but more likely it's something upstream of the sensor. It could be intake (air) related or fuel (injector) related.
In order to determine if indeed it is the sensor, swap both of the pre-cat sensors. Clear the code and drive until the code comes back up.
If the code refers to the left bank (2-6) then you know the sensor is bad.
If the code still shows up as right bank (1-3) then it's something upstream as explained above.
Happy Boxstering,
Pedro
Pedro Bonilla1998 Boxster 986 - 311,000+ miles:
[www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)
Racecar spelled backwards is Racecar
"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"
"If you wait, all that happens is that you get older"... Mario Andretti
"Being second is to be the first of the ones who lose" ... Ayrton Senna