Use of vehicle presence systems for powertrain responsiveness and saving fuel

A method and system relate to improving the powertrain responsiveness in a vehicle, while the fuel efficiency is maintained by preventing entry into or exit from power saving modes when oncoming traffic is detected. In one example, the power saving mode is prohibited in response to an indication of an oncoming vehicle of importance. In a second example of the power saving mode is maintained selectively in response to an indication of an absence of oncoming traffic.