The invention concerns a test kit comprising a testing program programmed to control an internal combustion engine for testing the internal combustion engine with the engine kept at a fixed load condition, provided with a test module programmed execute a sequence of individual cylinder tests, wherein the test module comprises first computer code for measuring, in each cylinder test, a first engine performance value and further comprises second computer code for providing an amount of fuel to one cylinder under test to differ from an amount of fuel provided to the rest of the plurality of cylinders; and a further test module programmed to measure, in an idle period between subsequent individual cylinder tests of said sequence of individual cylinder tests, a second engine performance value; and said further test module comprising third computer code to discard at least some of the individual cylinder tests if the second engine performance measured by the further test module value passes a threshold.

Aspects of the present invention relate to a method and to a control system for controlling an engine and an electric traction motor of a vehicle, the control system comprising one or more controllers, wherein the control system is configured to: receive an indication of engine speed during engine idling; and control the electric traction motor to reduce a difference between the engine speed and an engine idle speed target

A method and a system for adjusting a base idle speed of an engine are described. In one example, the method reduces engine speed according to output of a sensor that senses mechanical vibrations. Once a vibration level exceeds a threshold, engine speed reduction ceases and the base engine idle speed is adjusted according to a present engine speed.

A throttle body fuel injection system and method that is arranged to easily replace four-barrel carburetors includes a throttle body assembly with four main bores, each with a throttle plate and an associated fuel injector. Each injector feeds fuel into a circular fuel distribution ring via a fuel injection conduit, which introduces pressurized fuel into the air stream. The fuel distribution rings and bores have profiles that avoid constrictions for to prevent low pressure zones according to the Venturi effect. The throttle body includes an idle air control circuit having a port opening into main intake bores downstream of the point of fuel distribution into the air stream, thereby reducing the tendency for a lean fuel mixture at idle. An ECU “feed forward” algorithm controls fuel injection as a function of the position of the idle air control valve.

In at least some implementations, a method of controlling engine idle speed includes comparing engine speed to a speed threshold where the speed threshold may include a range of speeds, if the engine speed is outside of the speed threshold, adjusting the timing of an ignition spark up to a threshold amount of ignition timing adjustment, and if the engine speed is not within said speed threshold after adjustment up to the threshold amount of ignition timing adjustment then adjusting the air/fuel mixture provided to the engine to bring the engine speed within said speed threshold.

An engine idle reduction control apparatus includes a first data acquiring unit, a detecting unit, a first determining unit, a control unit, and a second determining unit. The detecting unit is configured to detect a traffic circle, on the basis of traveling environment data acquired by the first data acquiring unit. The control unit is configured to execute an idle reduction, in a case where the first determining unit determines that a control condition for a pre-stop idle reduction control is satisfied. The second determining unit is configured to determine whether a prohibition condition for the pre-stop idle reduction control is satisfied, in a case where the traffic circle is detected. The control unit is configured to prohibit the idle reduction even in a case where the control condition is determined to be satisfied, on a condition that the prohibition condition is determined to be satisfied.

A system according to the principles of the present disclosure includes an engine stall module and an actuator control module. The engine stall module identifies a potential engine stall based on a speed of an engine and a rate of change in the engine speed. The actuator control module selectively adjusts an actuator of a powertrain system to prevent the engine from stalling when a potential engine stall is identified.

A method of operating an internal combustion engine, and more particularly a fuel injector is disclosed. The fuel injector is commanded to inject a fuel requested quantity. The fuel requested quantity is adjusted by closed-loop for controlling an engine speed to match a target value thereof. A value of a first parameter indicative of an amount of electrical energy supplied to an electric battery by an electric generator coupled to the internal combustion engine is measured. A value of a voltage generated by the electric battery and a value of the engine speed are measured. A reference value of the fuel requested quantity is calculated on the basis of the voltage value, the engine speed value and the value of the first parameter. A difference between the value of the adjusted fuel requested quantity and the reference value is calculated and used to control the internal combustion engine.

A method for entering and exiting cylinder deactivation modes in a diesel engine, comprises monitoring an engine speed from an idle engine speed to a governed engine speed and monitoring an engine load. If the monitored engine speed is the idle engine speed up to the governed engine speed, and if the engine load is less than the predetermined low load condition, then implementation of a cylinder deactivation mode is restricted to one of a 2 cylinder deactivation mode, a 3 cylinder deactivation mode, or a 4 cylinder deactivation mode. A cylinder deactivation mode is selected for engine operation among the 2 cylinder deactivation mode, the 3 cylinder deactivation mode, and the 4 cylinder deactivation mode to operate the engine at an effective frequency that avoids two resonant frequencies of the vehicle and to operate the engine below a torsional vibration limit.

Methods and systems are described for engine idle speed optimization. A system may include determining whether a fuel intake rate indicative of an amount of fuel consumed by an idling engine over time satisfies a threshold in comparison to a reference fuel intake rate. The reference fuel intake rate may be indicative of a predetermined amount of fuel consumed by the idling engine over time. The system may adjust a predetermined minimum speed at which the engine idles in response to determining that the fuel intake rate satisfies the threshold.