Hi, I'm completing a project on a car involving oxygen sensors; which use a chemical element that reacts to the amount of air present to generate a small voltage that is sent to the car's ECU. The car's computer only has one input channel for one o2 sensor, but I'm adding a second o2 sensor. I know a little bit about relays, and I'm wondering what kind of circuit could take the small voltage output from two separate sensors, and switch between them a few times per second to output to the car's computer? The circuit would have to have minimal voltage loss since the voltage is already so low. Any help is greatly appreciated here.