Need to replace your AF Sensor on your Subaru? Here it is.

An ‘air-fuel sensor’ (also called ‘lambda sensor’ or ‘wideband oxygen sensor’) is simply a TYPE of oxygen sensor. Specifically, it is a type of oxygen sensor that is able to measure the actual amount of oxygen in the exhaust stream rather than simply finding the cutoff between stoichiometric and lean.

Air fuel ratio sensors are like an O2 sensor on steroids.

Oxygen sensors tell if the mixture is rich or lean, period. They can’t tell you how rich or how lean the mixture is.

An AF sensor can tell you the actual AF ratio out to about 18 to 1. This allows much finer tuning of the mixture.

Fitment: 2013+ BRZ