The good: The Vehicle Diagnostics system keeps track of your car's location and fuel level, and sends alerts for maintenance issues. Users can access data on the Web or through a smartphone app.
The bad: Without an existing Verizon data plan, it costs $35 per month to run the Vehicle Diagnostics system. It does not track fuel economy.
The bottom line: Delphi's Vehicle Diagnostics system works best as a tool for parents who let their kids drive the family car, as it shows the car location and will trigger an alert if the car leaves a proscribed area.