METHOD FOR DIAGNOSING FAILURE OF MAP SENSOR, CAPABLE OF APPLYING DELAY TIME AFTER PERFORMING THE FAILURE PROCESS SUBROUTINE IN DECIDING FAILURE

摘要

PURPOSE: A failure diagnosis method of a map sensor is provided to prevent stop of an engine from the uneven compound ratio by controlling the fuel amount with calculation of the air amount corresponding to sudden change of external signals and by applying delay time after performing the failure process subroutine in deciding failure. CONSTITUTION: An engine control unit decides failure of a map sensor by receiving signals from a vehicle state detecting unit(S100,S110), and detects the signal of the map sensor to be within the minimum and maximum range predetermined in a memory(S120). The map sensor signal and the engine load according to engine rpm are compared with the predetermined map sensor values(S130). The normality of the map sensor signal is decided, and the engine idle state is decided(S140). The clip value set by the memory is predetermined to the map sensor signal(S150). The required air amount is calculated in idling the engine, and the fuel injection control signal is output to the injector driving unit(S160).