What’s a PZEV?

The SI-DRIVE (Subaru Intelligent Drive) system is a state-of-the-art engine management technology, offering the driver different driving modes, depending on the circumstances or conditions. The SI-DRIVE is the ideal solution for drivers who want to combine sporty driving with fuel economy, and takes car performance to an unprecedented level. The Subaru WRX (CVT box) and the Subaru WRX STI both have the SI-DRIVE system, which has three modes: Intelligent (I), Sport (S) and Sport Sharp (S #). All Subaru Foresters from the 2019 model year are equipped with one of the two versions of the SI-DRIVE system, each comprising two distinct modes. The Forester Sport offers Intelligent (I) and Sport Sharp (S #) modes, while the other equipment versions offer Intelligent (I) and Sport (S) modes. As of model year 2020, all Subaru Impreza and Crosstrek models with CVT Lineartronic have the SI-Drive system with Intelligent (I) and Sport (S) modes.

The modes of the SI-DRIVE system

Intelligent Mode (I)

In Intelligent mode, the SI-DRIVE opens the throttle valve more gradually to maximize fuel efficiency, reduce emissions and provide smoother ride. The engine diagram also optimizes the acceleration and torque settings to maintain the most efficient settings, increasing overall fuel economy by up to 10%. For vehicles with the Lineartronic Continuously Variable Transmission (CVT), this mode automatically targets the most fuel-efficient ratio. All these characteristics make it the ideal setting for driving in an urban environment or when stops and departures are frequent. Intelligent mode is also suitable for problematic driving conditions, for example when driving in winter or on a gravel road.

Sport Mode (S)

Sport mode is the most suitable for everyday driving as it retains the most efficient engine and transmission settings under normal circumstances, but can provide precise engine response when needed. Here, the throttle opens more quickly compared to Intelligent mode, reacting more directly to the driver's maneuvers. This mode also allows smooth passages, uniform acceleration whatever the speed, solid overtaking power and overall road handling. As such, it is very suitable for highway and suburban streets as well as mountain roads.

Sport Mode Sharp (S#)

Sport Sharp mode harnesses the full potential of the SUBARU BOXER engine and transmission - and provides the most immediate response to driver maneuvers. This mode promotes an even more direct throttle response and precise control over the entire speed range, in addition to retaining lower gears longer on CVT models. The paddle shifters on CVT models give the driver better performance control thanks to eight programmed gear ratios, which reproduce the shifts of an eight-speed gearbox. The Sport Sharp mode is ideal for driving on winding roads and for confidently performing overtaking and engaging maneuvers on the highway.