Garmin has created a product to improve your driving efficiency and provide more engine diagnostic information. The product is a plug that fits into your existing for $149 Nuvi. The plug goes into your obd2 port for all cars that are 1996 and newer. It communicates wirelessly to your Nuvi to help improve your driving habits in terms of gas mileage and efficiency. The unit learns how you drive and provides preferred routing as well as scores you from 1-100 for efficiency. There are also 5 gauge pages that can be modified to provide real time information as well as read 4,000 trouble codes. The Nuvi 1260T, under $200, is the lowest cost Nuvi that will allow you to use the Eco Route.