PURPOSE: To control fuel injection appropriately without imapiring the engine performance, by controlling the fuel increasing and decreasing ratio according to the width of a datum fuel injection pulse by use of a means which controls the injection quantity of fuel through metering of air-flow rate, and making the air-fuel ratio lean in a low-load range to meet with the level of the load.
CONSTITUTION: When an engine is started with a key switch 15 and a starter switch 14 turned ON, calculation of a mainr outine is started and the temperature of cooling water is read from an analogue input port 204. The quantity of correction for fuel is calculated from the result of the above calculation and the result is stored in a RAM206. Then, a CPU200 proceeds to performing an interruption processing routine by a signal from an interruption control section 202, and a datum injection quantity of fuel Tp determined by engine speed N, air-flow rate Q and a constant F is calaculated deriving the engine speed N from an engine speed counter 201 and the flow rate Q of intake air from the input port 204. The load is detected from the value Tp and the mode of operation is selected. On the basis of this selection, each quantity of correction is read out from a ROM207 through judgement of increase, feedback or decrease of fuel. Then, the air-fuel ratio is determined from the quantity of correction obtained by the main routine.
NAGASAWA SHIROU
NIWA TAKAO
GOUNO TAKESHI
TOYOTA MOTOR CO LTD
| JPS5618035A | 1981-02-20 |