Excess air coefficient correction method and device, vehicle and storage medium

The invention discloses an excess air coefficient correction method and device, a vehicle and a storage medium. The excess air coefficient correction method comprises the steps that the excess air coefficient of an upstream wide-range oxygen sensor of a target three-way catalytic converter is obtained; a long-term deviation value between an actual voltage value of a downstream switch oxygen sensor controlled by an integral term in a proportional integral controller of an engine and a target voltage value and proportional term control information are obtained; a target self-learning mode of the downstream switch oxygen sensor is determined based on a long-term deviation value between an actual voltage value and a target voltage value of the downstream switch oxygen sensor and the proportional control information; the downstream switch oxygen sensor is controlled to obtain a characteristic deviation learning value of the downstream switch oxygen sensor for the upstream wide-range oxygen sensor in the target sel