ACDelco GM original equipment flex fuel sensors will tell you the composition of your fuel. How much ethanol is in your system? Well, you’re about to find out. These sensors measure the ethanol/gasoline ratio of the fuel being used—and then send a signal to your ECM so adjustments can be made for optimum operation of your flexible fuel vehicle. Allow ACDelco GM original equipment flex fuel sensors to provide the right answers for you to regain reliable, efficient performance.