Fire fault diagnosis device for engine

The utility model provides a fire fault diagnosis device for an engine. The fire fault diagnosis device comprises an engine management module, a fire diagnosis module and an OBD system management unit, wherein the engine management module comprises an engine state sensor input unit, a special condition judgment unit, a real-time diagnosis information unit, a rotary speed and load information unit, a trouble light control unit and serial port communication unit; the fire diagnosis module comprises an enabling condition judgment unit, a diagnosis mode judgment unit, a torque mode unit, an accelerated speed mode unit, a fire time and rate computing unit and a result judgment unit; and the OBD system management unit is connected with the result judgment unit and the trouble light control unit in the engine management module. The adoption of the fire fault diagnosis device for the engine can not only diagnose the fire fault existing in the engine timely, but also judge the cause of fire accurately.