Hello, If you have the California emissions package you have 2 O2 sensors (narrow band) upstream of your catalytic converter, so one of our dual Narrow Band EFIE?s be needed. If you have the federal emissions package then you have 1 O2 sensor (narrow band) upstream of your catalytic converter, so one of our single Narrow Band EFIE?s would work. We recommend or new ?Quad Digital EFIE Basic? to work with any narrow band sensor configuration.