oxygen sensors last... once they are replaced? 60k 80k or 100k? and do we have to replace the MAF once in a life time is there any interval mileage on MAF as well as on Oxygen sensors? i had my oxygen sensors replaced 25k ago so when am i expecting them to go bad again and should i replace all the sensors or just the one that is bad? i have not had my MAF replaced yet even though my car has 117k. should i replace the MAF or wait till the SES goes off?

 

Repalce them when they go bad. (SES light comes on and the code references any of the mentions sensors)

 

Isn't it possible for the MAF to be malfunctioning and the SES light to be off?

What are the symptoms of a bad MAF?