Disclosed are a hybrid electric vehicle capable of controlling starting of an engine in order to more efficiently realize heating and an engine control method therefor. The method of controlling an engine of a hybrid electric vehicle of the disclosure includes determining whether the engine is in a warmed-up state when a fully automatic temperature control system makes a heating request, making an engine startup request for heating to an engine management system configured to control the engine when the engine is in the warmed-up state, and selectively requesting the engine management system to perform cylinder deactivation (CDA) control on at least some of a plurality of cylinders of the engine depending on whether the engine is in an idling state.

A friction loss management system for an engine, comprises a combustion engine comprising a crankshaft and a plurality of cylinders, a reciprocating piston assembly connected to the crankshaft, a fuel injector, an intake valve, and an exhaust valve. A control unit comprises at least one set of control algorithms configured to receive engine power demand data, and determine a number of cylinders of the plurality of cylinders for deactivation based on the received engine power demand data and further based on sensed or stored friction values for the plurality of cylinders. Determining the number of cylinders of for deactivation minimizes friction between the plurality of cylinders and their respective reciprocating piston assembly by selecting a cylinder combination of active cylinders and deactivated cylinders with the lowest total friction while meeting engine power demand. All cylinders can be deactivated for purposes of coasting or controlling speed during platooning.

A method for controlling vehicle speed comprises selecting an engine speed profile for a vehicle. Road grade data is received and processed to determine a road grade for the vehicle. Vehicle speed data is received and processed to determine a vehicle speed for the vehicle. A cylinder deactivation mode for a valvetrain of a multi-cylinder engine of the vehicle is selected. The cylinder deactivation mode comprises deactivating one or more intake valve, exhaust valve, and fuel injection for one or more cylinder of the multi-cylinder engine. The selected cylinder deactivation mode provides a controlled deviation from the selected engine speed profile at the road grade and vehicle speed.

An overhead cam engine system comprises a rotating overhead exhaust cam rail comprising a plurality of exhaust lobes. A first switching roller finger follower actuates a first exhaust valve, and is configured to switch between a first lift profile and a second lift profile. A second switching roller finger follower is coupled to actuate a second exhaust valve, and is configured to switch between a third lift profile and a fourth lift profile. The third and fourth lift profile are different than the first and second lift profile. An actuation assembly is connected to switch the first switching roller finger follower and the second switching roller finger follower to select between at least three exhaust lift modes to open and close the first exhaust valve and the second exhaust valve using combinations of the first, second, third and fourth lift profiles.

When an amount of particulate matters (PM) collected by a gasoline particulate filter (GPF) increases, a control processing unit (CPU) of an engine electronic control unit (ENG ECU) stops combustion control of some cylinders and executes a regeneration process to cause air-fuel ratios of air-fuel mixtures in the remaining cylinders to be richer than a stoichiometric air-fuel ratio. A CPU of a hybrid electric vehicle electronic control unit (HV ECU) increases a target rotation speed of an internal combustion engine when the regeneration process is executed. When executing the regeneration process, the CPU increases a filling efficiency of the internal combustion engine.

Methods and systems are provided for an air system. In one example, a system includes a boost device configured to be driven by exhaust air from a plurality of cylinder in order to compress ambient air. The compressed ambient air is delivered to a tank configured to store compressed gases.

Methods and systems are provided for enhancing turbocharger performance for a boosted engine system configured to operate with a pattern of deactivated cylinders. In one example, a method may include, in response to a demand for boost, operating with a cylinder pattern based on boost demand and turbocharger configuration. The specific pattern may depend on the pattern constraints imposed by engine load and NVH metrics.

A method for controlling a supercharger of a vehicle includes: determining, at a first determination step, whether or not an engine operates in a cylinder deactivation (CDA) mode; calculating, at a second determination step, a difference value between a target boost pressure of a turbocharger and a current boost pressure of intake air boosted by the turbocharger, and determining whether or not the difference value is equal to or greater than a reference difference value; determining, at a third determination step, based on a current operating condition of the engine whether or not the supercharger is allowed to operate; determining, at a fourth determination step, a target rpm of the supercharger, and determining whether or not the target rpm is equal to or greater than a reference rpm; and operating the supercharger at an operating step.

Systems and methods for determining fuel delay in a fuel injected engine with cylinders that may be deactivated are presented. In one example, the fuel injection delay is determined via a cylinder firing schedule array when the cylinder firing schedule array is available. The fuel injection delay is determined via weighted average of a fuel injection delay of a present engine cycle and a fuel injection delay of a past engine cycle when the cylinder firing schedule array is not available.

Methods and systems are provided for estimation of a road roughness index (RRI) and adjusting vehicle operation based on the metric. In one example, a method may include estimating the RRI as a function of a pitch energy and a roll energy of the vehicle travelling on the road. In response to the RRI being higher than a threshold, engine operation such as EGR flow rate may be adjusted.