Sketch and describe an overview of the electronically controlled camshaft-less engine with respect to the following operations:

[Sketch notes: The fuel injection system consists of: (1) a fuel supply system (fuel pump, fuel rail); (2) a fuel injection valve (injector) in each cylinder; (3) a hydraulic (servo) oil system; (4) a solenoid valve; (5) the electronic control unit (ECU).]

In a camshaftless engine, the fuel injection is controlled electronically. Each cylinder has a fuel injection valve (injector) which is opened hydraulically. The ECU determines the injection timing and quantity (based on engine speed, load, and other parameters). At the commanded crank angle, the ECU energizes a solenoid valve, which admits high-pressure servo oil to the injector, opening the needle and injecting fuel. The injection duration (quantity) is controlled by the time the solenoid is energized. The injection timing can be varied (VIT) and the injection profile can be shaped (e.g. pilot injection) by the ECU. There is no camshaft to drive the fuel pump; the injection is fully controlled by the ECU.

[Sketch notes: The exhaust valve actuator consists of: (1) a hydraulic actuator (piston) on the exhaust valve; (2) a solenoid valve; (3) the servo oil system; (4) the ECU; (5) an air spring to close the valve.]

In a camshaftless engine, the exhaust valve is opened hydraulically and closed by an air spring. The ECU commands the exhaust valve timing (opening and closing) by energizing a solenoid valve, which admits servo oil to the hydraulic actuator, opening the exhaust valve. When the oil is released, the air spring closes the valve. The exhaust valve timing can be varied (e.g. for the Miller effect or for load control) by the ECU. There is no camshaft to drive the exhaust valve; the timing is fully controlled by the ECU.

[Sketch notes: The cylinder lubrication system consists of: (1) a lubricator pump (or servo-driven lubricator) for each cylinder; (2) a control unit; (3) the oil supply; (4) the injection points on the liner.]

In a camshaftless engine, the cylinder lubrication is controlled electronically. Each cylinder has a lubricator (or a set of lubricators) which injects the cylinder oil onto the liner. The control unit determines the oil feed rate (based on the engine load, speed, and fuel sulphur) and the injection timing (relative to the piston position). The lubricators are driven by servo motors (or by the hydraulic system) and inject the oil at the correct time and quantity. The feed rate can be adjusted (two-level lubrication) to match the load and the fuel sulphur, reducing oil consumption and deposits. There is no mechanical drive from the camshaft; the lubrication is fully controlled electronically.