The way of CU modification ECU chip modification car factory has already burned the previously set fuel supply program on the ROM when designing an engine. This program is usually the product of compromises on fuel consumption, pollution, smoothness of operation and other conditions, and is immutable. Because it cannot be changed, if you want to change the fuel supply program, you must switch to another ROM. Usually professional refitting factories will supply computer chips for refitting various models. When refitting, you must first remove the original computer chip (usually the ROM of the original fuel supply computer is directly welded on the circuit board), and solder an IC seat (such It will be convenient to replace in the future), and then plug in the chip for modification. The fuel supply program obtained in this way is still fixed, and it is only a modification of the original car program. One of the most important items is that the fuel cut-off control time in the compensation injection program can be delayed or even canceled. . It should be noted that each modification chip has its applicable conditions (that is, the degree of modification). When modifying, you must choose a chip that is similar to the modification status of your car in order to get the best results, otherwise it may be counterproductive.