# The Indicator of GDI Engine Operating Mode and Its Influence on Eco-Driving
## 1 Introduction  
An in-depth understanding of the human factor aspects of car driving operations is necessary, as they are responsible for safety [1; 2] and affect the environment. Unfortunately, it is not easy to assess the influence of particular aspects of every single factor because of the complexity of human general and especially the technical knowledge, environmental awareness, motivation and behaviour. It is challenging to analyse how a driver's personality, temperament, mental and physical condition influence driving. In addition, the habits that drivers have when operating vehicles, such as preferred speed and rate of acceleration, are very important [3]. They all impose a significant impact on vehicle functioning and its effective use. Fuel consumption is critical and strongly affects air pollution and contributes to the greenhouse effect. It is possible to try to analyse the impact of the experience and skills of the driver in the driving of the vehicle and, if necessary, change them through training [2; 4]. We usually do not consider people's self-perceptions about their driving style or the associated beliefs. Around 50% of the participants in the research described in [5] said they were trying to eco-drive or were eco-drivers. From this point of view, people need some tools to realise their needs. The car's construction is too complicated to understand all mechanisms and their functions in environmental protection. Still, fuel consumption and its direct impact on the environment are explained easily. As is the case with an internal combustion engine, the rational and ecological use of energy strongly depends on the driver's behaviour [6]. Elements of car construction, especially the information available on a dashboard, can stimulate it. The studies that focused on driver support in eco-driving presented in [7] describe the assistance system that advises the most fuel-efficient accelerator pedal angle in real time. The authors concluded that the haptic force feedback via theaccelerator pedal is the most effective interface. The proposal of a driver support system is the \"driving coach\". It collects, fuses, and analyses diverse information, such as a digital map, weather, traffic situation, and vehicle information, to provide drivers with in-depth information regarding their previous trip along with personalised hints to improve their fuel-efficient driving in the future [8]. The algorithm for determining routes that cause the least fuel consumption was described in [9]. The core of this algorithm is a specific EEC (energy efficiency constant) map containing logic that can predict fuel consumption. The android application, which provides several innovative properties--advice according to upcoming events, a real-time evaluation of the driving behaviour, the analysis of past actions, and an interface with OBD2 connector--is described in [10]. These measures increase drivers' ability to implement eco-driving, significantly affecting fuel consumption. They may cause a reduction in fuel consumption even by up to 15% [11]. Modern vehicles are equipped with the fuel-cut function. The fuel is not injected when the driver does not press the gas pedal of a vehicle with engine speeds higher than approximately 1500 rpm above the mid-vehicle speed range. Such a solution enables about 4% fuel savings [12]. In currently produced passenger cars, eco-driving indicator lights are installed. The vehicle speed, engine speed, and throttle position influence the indicator light. Depending on the type of vehicle, the throttle responsiveness, transmission gear shifting, or electric systems are tuned to reduce fuel consumption. Generally, the light indicator turns on (usually green) when the engine operates close to its minimum specific fuel consumption, influenced by many factors. An interesting issue is the attempt to describe how information about the engine mode run influences the driver behaviour and fuel consumption. This paper is devoted to this issue.