The control unit is nothing more than a special computer that controls the operation of all vehicle systems. If it's a computer, it's based on microcircuits or chips. Chips are program carriers that are written and installed at the factory where the car is assembled.
This setup method actually changes various program and controller settings. There are different software tools to do this. As a result, after the changes are made, the performance of the power unit improved and some car owners claimed that they could get the full potential of the engine.
This is done by programmers who know and understand the operation and algorithms of the ECUs of various brands and models and can make the necessary changes to improve performance. You can also check the benefits of remapping through multiple sources.
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The result of this procedure does not depend on the technological capabilities but on the person who is performing this job. If he does not understand the nuances of a certain engine function, then such a procedure has no advantages, and the car owner will receive continuous disadvantages.
However, attentive readers will notice that if the motor runs at high power, then there is no need to change any setting right now. Experts say you shouldn't be afraid to increase your fuel consumption. Increasing the power in no way increases the "appetite" of the engine.