DIY : changing the Oxygen / O2 sensor on Yaris hatch MANY PICS

[07liftback]

Originally Posted by Cigar_Maverick

Honestly, I'm trying to remember if I unhooked the battery or, more likely, went to the local parts store and had them clear the errors. Almost certain I just had the codes cleared. No errors since.

Did mpg improve right away?

[Cigar_Maverick]

Originally Posted by 07liftback

Did mpg improve right away?

Unfortunately, that is hard to say... The weekend I put the new one in, I also switched to Mobil 1 synthetic Advanced Fuel Economy, put a new air filter in and new plugs. I had just bought the car and didn't know the maintenance history. The total gained me 2.5 MPG. Going from 37.5 to 40. I am led to believe that, in my situation, the new sensor has minimal effect. That having been said, as they say, your results may vary. In hindsight I might have done a more controlled experiment, but I just hammered it all out at once. Maybe somebody else can chime in who has more experience with just installing the new sensor.