Like it or not, modern automobiles heavily rely on computer controllers to achieve:
- Meet tailpipe emission standards defined by OBD-II
- Safety features, Anti-Lock Braking, Obstacle Avoidance, Suspension Tuning, ...
- Interior climate control
- High Performance, e.g. modern cars car achieve over 600 HP, have decent gas mileage, are reliable, and smog legal
So, to maintain and enhance modern automobiles you need a descent understanding of the four stroke motor and computer control systems. This section will give a high level explanation of computer control systems.