Modern cars are complex things and rely on a number of computers to run properly. What you may not know is that these computers can often lead to your car feeling different after a service or repair.
Throughout the early days of the automobile, cars relied on a number of mechanical systems to be able to feed the right amount of fuel into the engine, to apply the right amount of pressure to the brakes, and to select the right gear to be in while driving. However, these systems were often bulky, required extra maintenance and were unable to compensate for ever changing environments.
As the world became more and more technologically advanced, car manufacturers began to realise that computers were the future for controlling cars in real time. It made them easier to maintain and helped them run smoothly in all conditions, from desert heat to freezing sleet.
Further improvements and testing brought about the very first electronic engine management system. These early ECM (electronic engine management) systems were not complicated by today’s standards and were likely not even as powerful as a smart phone. However, they provided constant and consistent engine management and vastly improved not only cars but the owner's experience.
As with all technology, these systems continued to progress at a rate of knots and soon these little computers were being used to control everything from the radio to the brake lights.
As the systems were improved, important standards came into play, including CAN-BUS and OBD. However, none of these updates made more of a difference to driving than fuzzy logic.
Fuzzy logic is the idea that, instead of a yes/no or on/off signal, computers can produce an answer between 0 and 1 based on how you drive the car every day. For example, if one person uses 100% throttle all the time (accelerating and braking heavily) they probably prefer a very responsive throttle.
Whereas a person who drives limousine services would only use small amounts of throttle, so wouldn't want the jerkiness that comes with accelerating hard all the time.
To achieve this, vehicle manufacturers allow computers to operate inside of a window, collecting data about how you drive and changing the characteristic to match your particular style. This is fuzzy logic in a nutshell.
While fuzzy logic is an awesome feature brought to us by technology, it can be confusing to owners as well, as when you buy a new car it may start to drive differently to when you bought it.
Overall, this can often confuse new car owners but is actually nothing to be concerned about. The only thing that we would like to see more of as mechanics, is sales staff that let you know about fuzzy logic.