What is an EFIE?

The EFIs fitted to cars are able to tell us if the air/fuel ratio is either rich or lean, but it doesn't tell us how rich or how lean the mix is.

Up until relatively recently, all oxygen sensors were of a type known as narrow band sensors. The reason these sensors are called "narrow band" is because they are only able to tell us if the air/fuel ratio is above or below a single known amount or a single narrow range. It can tell us that the mix is either rich or lean, but it doesn't tell us how rich or how lean the mix is. 

For the majority of these sensors, we use with Delux Dual EFIEs. and these sensors make up the majority of the sensors in America, but for the Japanese cars made after 1997, they will need Wide Band EFIEs. 

Wide band oxygen sensors are also called wide range oxygen sensors, air fuel ratio (AFR) sensors, or just A/F sensors. They are called "wide band" sensors due to the fact that unlike narrow band sensors, they are not only able to tell the computer if the air/fuel mix is rich or lean, but how rich or how lean it is. 

These sensors are new, and weren't used in any vehicles prior to 1997. Starting in about 1999, nearly all Toyota models started using them. However, other than various Japanese and German makes, most automobile manufacturers have yet to adopt them.

For more advice give us your car details and we will get back to you with our recommendations.