What is the reason for the negative ignition advance angle?

The reason why the engine ignition advance angle of Pacific Auto Network is negative is that the knock sensor is faulty. If the ignition advance angle is always negative, it means that the engine ignition is in a delayed state. It may be the poor antiknock performance of gasoline or other abnormal problems of the engine.

Ignition advance angle function:

The mixture in the cylinder burns at a certain speed, that is, it takes a certain time for the spark plug to ignite and the combustible mixture in the cylinder to burn completely. However, due to the high speed of the engine, the crankshaft can turn a large angle in such a short time. If the ignition happens just when the piston reaches the top dead center and the mixture begins to burn, then the piston has already started to move downward, resulting in a decrease in engine power. Therefore, it is necessary to ensure that the energy generated by combustible mixture can be effectively utilized by early ignition to improve the output power of the engine.

When the throttle opening, speed and mixture concentration of gasoline engine remain unchanged, the power and fuel consumption of gasoline engine change with the change of ignition advance angle. There is an optimal ignition advance angle for each working condition of the engine.

Proper ignition advance angle can make the engine do the most mechanical work per cycle (the shaded part of the curve). The ignition advance angle is too large, which is easy to deflagrate; Influence of Ignition Advance Angle on Maximum Combustion Pressure of Engine If the ignition advance angle is too small, the exhaust temperature will increase and the power will decrease. (Photo/Text/Photo: Pacific Auto Netscape Chen Chen)