When to replace ox sensor?

[Russell]

I get conflicting information on this. Some say 100,000 miles, others say change at 60,000. I have also heard the term "lazy sensor" which I think indicates a slow response to fuel /air adjustment needs.

I have no known problems. However, I am into preventative maintainance and I have almost 60,000 on this sensor.

BTW, I have heard from my indy to always use an OE Bosch O2 sensor. For some reason they seem to have a lower failure rate than OEM/aftermarket bosch sensor. Not proven.

TIA

[shogun]

Well, Bentley repair Manual has the instructions to check the oxy sensors.

First thing I would do, is to check the looks of the sensor, as it will tell you a lot.
A mileage where it get's bust is not lcear, depends on conditions. Here is what Walker says
http://www.oxygensensors.com/diagnose.jpg

I just bought oxy sensors from Autohausaz at a good price of $ 63.10 for the 750 and I will install them soon. No problems with the old ones, but I want to check if new ones work better = which I somehow can see/recognize/feel = less fuel consumption etc.
Maybe waste of money, but here in japan they cost >$ 300/each and I need 2 per car on my 2 750. :(

[Russell]

may just replace as you suggest-thanks