The present invention relates to a manifold for receiving exhausts from a multi-cylindrical internal combustion engine. The internal combustion engine has such a firing order that the riser in the manifold receives exhausts from two cylinders during an overlapping stage, simultaneously via an inlet opening arranged upstream and from an inlet opening arranged downstream in the riser. The riser comprises a substantially constant cross sectional area, except in one area, which is located in a position in connection with the inlet opening arranged downstream of the two inlet openings, receiving exhausts simultaneously. Said area has a geometry facilitating receipt and flow of exhausts in the predetermined direction in the riser, on occasions when the two inlet openings receive exhausts simultaneously.

The present invention relates to a manifold for receiving exhausts from a multi-cylindrical internal combustion engine. The internal combustion engine has such a firing order that the riser in the manifold receives exhausts from two cylinders during an overlapping stage, simultaneously via an inlet opening arranged upstream and from an inlet opening arranged downstream in the riser. The riser comprises a substantially constant cross sectional area, except in one area, which is located in a position in connection with the inlet opening arranged downstream of the two inlet openings, receiving exhausts simultaneously. Said area has a geometry facilitating receipt and flow of exhausts in the predetermined direction in the riser, on occasions when the two inlet openings receive exhausts simultaneously.

A crankshaft in which vibrations can be damped effectively without changing a design of a crankcase. The crankshaft comprises a first crank section located at one end of the crankshaft, and a second crank section located at the other end of the crankshaft. In the first crank section, a mass of a first inner balance weight is greater than a mass of a first outer balance weight. In the second crank section, a mass of a second inner balance weight is greater than a mass of a second outer balance weight.

A crankshaft in which vibrations can be damped effectively without changing a design of a crankcase. The crankshaft comprises a first crank section located at one end of the crankshaft, and a second crank section located at the other end of the crankshaft. In the first crank section, a mass of a first inner balance weight is greater than a mass of a first outer balance weight. In the second crank section, a mass of a second inner balance weight is greater than a mass of a second outer balance weight.

Intake noise suppression techniques for a forced-induction engine having a low pressure exhaust gas recirculation (LPEGR) system configured to recirculate exhaust gas produced by the engine to an intake system of the engine via an EGR port comprise receiving, from a mass air flow (MAF) sensor of the engine, a MAF signal indicative of measured airflow through the intake system, detecting, based on the MAF signal, intake system conditions that are indicative of audible noise, and in response to detecting the detected intake system conditions that are indicative of audible noise, at least partially closing a differential pressure (dP) valve to mitigate or eliminate the intake system conditions and the corresponding audible noise, wherein the MAF sensor is disposed in the intake system upstream from the dP valve.

Intake noise suppression techniques for a forced-induction engine having a low pressure exhaust gas recirculation (LPEGR) system configured to recirculate exhaust gas produced by the engine to an intake system of the engine via an EGR port comprise receiving, from a mass air flow (MAF) sensor of the engine, a MAF signal indicative of measured airflow through the intake system, detecting, based on the MAF signal, intake system conditions that are indicative of audible noise, and in response to detecting the detected intake system conditions that are indicative of audible noise, at least partially closing a differential pressure (dP) valve to mitigate or eliminate the intake system conditions and the corresponding audible noise, wherein the MAF sensor is disposed in the intake system upstream from the dP valve.

A method for operating an internal combustion engine having multiple cylinders. A warm-up operation is carried out after the internal combustion engine has been started, during which a speed of the internal combustion engine is limited to a limit value. The limit value is selected during the warm-up operation at least temporarily as a function of a starting temperature of the internal combustion engine.

A method for operating an internal combustion engine having multiple cylinders. A warm-up operation is carried out after the internal combustion engine has been started, during which a speed of the internal combustion engine is limited to a limit value. The limit value is selected during the warm-up operation at least temporarily as a function of a starting temperature of the internal combustion engine.

A fuel pump pressure-feeds fuel to an accumulation container that accumulates high-pressure fuel. A fuel injection valve injects high-pressure fuel accumulated in the accumulation container to an internal combustion engine. A fuel pressure sensor detects a fuel pressure in the accumulation container. A fuel pressure acquisition unit acquires the fuel pressure detected with the fuel pressure sensor. A reference computation unit computes a required injection quantity and an injection start timing based on an operation state of the internal combustion engine at a predetermined reference computation timing, which is set for each combustion cycle of the internal combustion engine, and further to compute an injection time period based on a fuel pressure acquired by the fuel pressure acquisition unit at the reference computation timing. A correction unit corrects the injection time period based on the fuel pressure acquired by the fuel pressure acquisition unit at the injection start timing.

A fuel pump pressure-feeds fuel to an accumulation container that accumulates high-pressure fuel. A fuel injection valve injects high-pressure fuel accumulated in the accumulation container to an internal combustion engine. A fuel pressure sensor detects a fuel pressure in the accumulation container. A fuel pressure acquisition unit acquires the fuel pressure detected with the fuel pressure sensor. A reference computation unit computes a required injection quantity and an injection start timing based on an operation state of the internal combustion engine at a predetermined reference computation timing, which is set for each combustion cycle of the internal combustion engine, and further to compute an injection time period based on a fuel pressure acquired by the fuel pressure acquisition unit at the reference computation timing. A correction unit corrects the injection time period based on the fuel pressure acquired by the fuel pressure acquisition unit at the injection start timing.