This is a challenge, since in order to get these information from your car is to buy an OBD2 scan tool which is about $24 on Amazon. Normal people don't know what OBD2 is and will not spend money unless there is a good reason for it. So this is what I propose. Let's make it a game since people love game especially if that helps them save money.
Application will have to be a mobile app. Mobile App that integrate with Google Map and perhaps GPS. Drivers can login with Facebook connect or register with username, email and few car info. This app will have four screens. First screen will allow you to set a location, start and end, i.e. my work place and home with 'Start' button to start the game. Second screen will show the user's progress. Third screen will show how they did compare to previous records and other drivers. Fourth screen will show who is driving most efficiently such as fuel efficiency, torque, and etc. It will use an algorithm using open data specs from the ODB2 scan information. It will rank today's winner and so on. They can see what car you are driving but all they know about you will be your car information and your username.
By creating this into a game drivers will use this data/app more often which will reduce traffic by not breaking too much, save gas, and make commuting little more enjoyable.