Routine O2 oxygen sensor replacement?

[tomjonesBT33]

I was reading through the service manual last night and saw that BMW recommends that the O2 sensors be replaced every 100K miles in order to maintain emissions performance and improved gas mileage.

My car is at 219K miles and they have never been replaced. No codes. Just passed emissions and safety in January. I also tend to average about 23mpg commuter mileage (mix of highway speed and stop and go). Pure highway mileage is 31-32 mpg.

Just wondering if you folks with higher mileage cars change the sensors as a matter of routine per the BMW recommendation.

Parts alone are $350 USD to replace all four.

Thoughts or experiences?

 

[srhutch]

New one on me. I'd leave them alone.

If they ain't broke (which they do) then don't fix it.

 

[colb]

Agree, if they work leave them alone, always worth having a look at them in live data with diagnostic software, Pre Cat should give you a wave pattern in a graph display as they range up and down their voltage. With age these can get a little slow to react but as long as they range up and down they should be fine. The post cat sensors don't range as much and will look almost static only showing slight change in voltages depending on r.p.m.. All this assuming you engine is running as it should.