Correction of idle speed depending on battery voltage and electrical energy balance
The engine idle speed correction compensates for the voltage drop when the power consumer is switched on if the battery is weakly charged. The correction begins when the voltage becomes less than 13 V. As a result of the correction, the engine speed can be brought to no more than 990 min⁻¹ for the F4P engine and 910 min⁻¹ for the K4M engine.
Connection between the power steering pressure relay and the injection system ECU
The injection system ECU receives information from the power steering pressure switch and can increase the idle speed to compensate for energy consumption.
Idle speed is increased to 770 min⁻¹ for the F4P engine and 750 min⁻¹ for the K4M engine.
Correction of idle speed depending on information from the electric windshield heater
If the heated windshield is on and the coolant temperature is below 60°C, the idle speed is set to 990 min⁻¹ for the F4P engine and 910 min⁻¹ for the K4M engine.
Correction of idle speed in case of faulty accelerator pedal position sensor
If there is no signal from both conductive tracks of the accelerator pedal position sensor, the engine speed is increased to approximately 2000 min⁻¹ and when the brake pedal is pressed, the engine switches to idle mode.
Correction of idle speed in case of malfunction of the throttle valve unit with servo drive
If there is no signal from both conductive tracks of the throttle position sensor, the throttle unit switches to the mechanical throttle opening limitation mode. In this case, the engine runs at 1900-2200 rpm.
Note: After starting a cold engine and idling for a long time, the engine speed may drop sharply for approximately 80 min⁻¹ for the F4P engine and 160 min⁻¹ for the K4M engine. This occurs due to the use of an automatic starter in the system.
| Coolant temperature,°C | -20° | 20° | 40° | 80° | 100° | 120° |
| Engine crankshaft speed, min⁻¹ (F4P) | 1070 | 980 | 900 | 750 | 750 | 850 |
| Engine crankshaft speed, mim⁻¹ (K4M) | 1120 | 900 | 820 | 750 | 750 | 900 |