Impact of altitude on the fuel consumption of a gasoline passenger car

Engines of new passenger cars are tuned at the sea level. However, in several countries, a significant part of the engine operation is performed at higher altitudes than that of the sea level. The different air density can have a significant impact on fuel consumption. In the case of gasoline engines, the higher altitude theoretically leads to lower fuel consumption due to lower throttle frictions due to the wider throttle opening. From the other side, as the air is less dense at higher altitudes, the vehicle aerodynamic is changed and this also leads to lower fuel consumption. This work studies the impact of high altitude on the fuel consumption of a gasoline passenger car. The impact of higher altitude is studied on three regulated driving cycles. The impact of changed vehicle aerodynamics of higher altitudes, through the change of deceleration times, on fuel consumption is also estimated.