Oxygen Sensor

We have a 2007 Nissan Versa with around 40,000 miles.
At 18,000 miles we were told we needed a new Oxygen sensor, which was covered under warranty, now at 40,000 miles we have the exact same problem, this time it is not covered and will cost around $300, and has a 1 year or 18,000 mile warranty. seems to me it is going to be an expensive fix every 20,000 miles or so to replace Oxygen sensor.
Any one else having this problem

$300!
Why so much?

We took the car into Suburban of Farmington Hills as SES light on, there's $165 to start with just for them to look at it, then $112.71 for the air sensor and $165 labor, my wife likes the car, but I can't say I would ever consider a Nissan again based on cost of ownership there are multiple recommended services and none of them are cheap, and that is before the SES light decides to kick in on a regular basis.

you probably have a lemon; no way would an oxygen sensor go that bad early in it's lifetime...

My sister has a 2007 Versa with 34k miles. The service engine soon light came on. The PCM is throwing code 2A00, B1 A/F .. I assume that is the Ox sensor. I wish I had gotten her a Chevy Cobalt instead. She lost a key now only has one . The dealer wants 100's of $$ for a second key. When we bought the car the dealership tried that Dealer profit trick.

O2 sensor should not be going bad so soon. Also, if you want to save some scratch, you can get your O2 sensor from places like Partstrain.com and install it yourself. I have seen O2 listed there for as low as 25.00 to 128 for Bosch. Good luck with your problem and try and give us an update.

there is a TSB out on the 02 sensors, not only does it need to be replaced they have to update the cars computer.