Under normal circumstances, the normal range of the ignition advance angle is between 6 and 12 degrees, but generally, most engines are set with an ignition advance angle between 5° and 30°. Ignition advance refers to the spark plug firing before the engine piston reaches the top dead center (TDC) of the compression stroke. The angle through which the crankshaft rotates from the moment the spark plug fires until the piston reaches the TDC is called the ignition advance angle. Reasons for ignition advance angle: Since it takes a certain amount of time for the flame to propagate and completely burn the combustible air-fuel mixture in the cylinder after the spark plug fires, and the engine operates at high speeds, if ignition were to start exactly when the piston reaches TDC, the mixture would begin to burn completely only after the piston has already started moving downward. This would result in a loss of gas thrust and ultimately reduce engine power. Therefore, modern engines are designed with an ignition advance angle. The angle through which the crankshaft rotates from the moment of ignition until the piston reaches the TDC allows the engine to achieve optimal power, fuel efficiency, and emissions. If the spark plug fires before the piston reaches TDC, the combustible mixture can burn completely by the time the piston reaches TDC (theoretically, peak gas pressure occurs best at 10°-15° after TDC). This significantly reduces the loss of gas thrust, thereby enhancing the engine's power output. Methods for adjusting ignition advance angle: It is recommended to visit a 4S shop for adjustment, as attempting to adjust it blindly on your own may have the opposite effect. Since adjusting the ignition advance angle requires extensive testing and debugging tools, as well as a solid foundation of automotive theoretical knowledge, it is advisable to take your vehicle to a 4S shop if there are any issues with the ignition advance angle.
