Review on Denso 234 9056 Fuel Ratio Sensor by Adam Hogan

This is an OEM replacement for the front air/fuel sensor (similar to the oxygen sensor) on the 07 Prius. The exchange was a bit cumbersome as there are no instructions on the internet. Here's how I replaced it: 1. Remove the wiper assemblies (two 14mm nuts for the passenger side wiper and 1 14mm nut for the driver side wiper. 2. Remove the plastic wiper pan (two reusable Plastic rivets, one for passenger side and one for passenger side) one on driver side) 3. Remove wiper motor assembly (6 screws 10mm, 1 electrical connector) 4. Remove wiper motor mounting shell (6 more screws 10mm) 5 Locate the air/fuel sensor on the driver's side of the exhaust manifold To remove you will need a special Toyota oxygen sensor wrench as no other wrench will fit the built in heat shield your stupid tool and lo and behold!