If the spark occurs either too early or too late in the cycle (i.e. if the ignition timing is off), the fuel will not ignite at the right time, and this can cause all sorts of problems.

• 如果火花在循环过程中产生得过早或过晚（比如点火的时间太晚），燃料就无法在正确的时间被点燃，这就可能导致各种类别的问题。