I've been looking online to see how often you need to replace the oxygen sensor for the 3rd gen Prius. I can't find anything online. Anyone know how often you replace these? Would it be around 100,000 miles or more because it's a hybrid? Also how many are there? I've heard there is 2 and some say there's 4. Thanks
When they fail. Don't worry about it until they do, and don't replace any more than the failed unit if one does. You car has one Air-fuel ratio sensor and one oxygen sensor. The former has more range than the latter.
And if/when you replace either one - make SURE you order and get the correct one - a lot of these "aftermarket" suppliers don't know the difference between the 2. (Yes, the voice of experience).
