if u use a product of an american company, u do not need change the sensor. it just cost u $30, and also save ur fuel.so,actually it does not cost u any money.
call me at (514)9692689 Mr. zheng
or email me at : zgofmontreal@gmail.com
the best way to deal with this problem is to use FFi product for one month .that product can save ur fuel and reduce carbon build-up,as a result, clean the sensor.(i saw somebody clean sensor for $200-300, it's naive)
after that, if it does not work, u should go to repair it.
yes, if u like, go to check the code first.