Engine Control System 1A-19 Idle Speed (P.N Range in A/T Vehicle) [ r/min] Legend 1. Engine 2. Pump 3. Injection waveform 4. Cam angle signal 5. Crank angle reference position signal 6. Actual compression TDC b. Feedback control Timing control valve duty ratio is calculated so that the actual injection timing coincides the target injection timing. Idle Speed Control Idle speed is controlled by increasing or decreasing the specified fuel injection amount value based on the signal from ECM (engine control module). Operation 1.
Feedback control When there is a difference between the target speed calculated by the ECM and engine speed at the idle speed, the fuel injection amount is controlled by changing the signal to the electromagnetic spill valve and controls so that the engine speed coincides the idle speed. 2. Warm-up control Optimum fast idle engine speed is controlled at idling by the coolant temperature. 3. Estimated control Immediately after changing over the air conditioning switch, before the engine speed changes, the injection amount is changed by a constant amount to prevent change of idle speed by the change of load given to the engine.
6 θ 1 5 θ 4 2 3 LNW21ASH001701 M/T A/T Engine speed at no load Approx. 580 Approx. 650 Air conditioner system ON Approx. 800 Approx. 870