I use a lot of ESP32 boards around my home, but they don't always have to be stuck indoors. By putting an ESP32 in my car, I'm able to access live engine data from my car that tells me much more than my dashboard does. Your car's OBD-II port can tell you a lot Mechanics aren't the only ones who can access live engine data The On-Board Diagnostics II (OBD-II) port is a 16-pin diagnostic port that mechanics can use to communicate with a car's computer. They can pull information from the computer to try to determine the cause when your car has a problem. Normally, a lot of the data they can access isn't available through your car's dashboard. One common reason for using this port is to extract error codes that can help narrow down car issues, but the port can also expose a lot of useful measurements, such as coolant temperature, engine speed, throttle position, intake temperature, engine load, and more. The port itself carries the data but also provides power to the connected scanner. The scanner can then pull data from the car's computer when the relevant systems are active. Mechanics aren't the only people who can access this data. You can do the same yourself, and it's surprisingly cheap to do. A cheap adapter can pull the information from the port You can buy one for just a few dollars OBD-II adapters plug into the OBD-II port of your car, which is usually found under the dashboard on the driver's side. These cheap adapters can pull the information from your car's computer and share it over Bluetooth. You can buy one for as little as $7. I bought one of these cheap adapters for my car, which is an aging Volkswagen. It was simple to