Altitude correction factor obtaining method and device

The invention discloses an altitude correction factor obtaining method and device, and belongs to the field of vehicles. The method includes the steps of obtaining the initial value of a filter when preset events happen to a vehicle engine, wherein the preset events include power-down events, power-up events and abnormal power failure events; judging whether a vehicle meets preset self-learning enabling conditions according to the rotation speed of the engine, the running speed of the vehicle and state information of specific equipment; enabling an altitude correction factor self-learning filter if the vehicle meets the preset self-learning enabling conditions; determining a filter input value at least according to the work state of a manifold pressure sensor and the work state of a stepping motor; carrying out self-learning of the altitude correction factor by means of the altitude correction factor self-learning filter according to the initial value of the filter and the filter input value, and obtaining a current altitude correction factor. The method and device improve accuracy of the altitude correction factor and improve idling stability.