Yes, combining computer science and car mechanics is an excellent idea, especially with the rise of automotive technologies like self-driving cars and smart diagnostics. This intersection is often referred to as automotive software engineering or automotive mechatronics.
Applications include developing software for engine control units (ECUs), designing autonomous driving systems, and creating diagnostic tools that analyze vehicle performance in real-time. Knowledge of car mechanics can help you better understand the physical systems you are programming.
You can start by learning embedded systems programming, robotics, and automotive-specific frameworks like ROS (Robot Operating System). Open-source projects like OpenPilot provide hands-on opportunities to explore this fascinating domain.