Abstract: The supercharge pressure and the pressure differential which develops between the supercharge pressure and the exhaust gas pressure upstream of a turbocharger turbine are monitored. In the event that the supercharge pressure is below a target level which is determined to optimal for the instant set of operating conditions, a first injection reduction amount is calculated. To allow for the effect of very sudden accelerations wherein the pressure differential tends to become large and the charging efficiency of the engine tends to reduce, a second reduction amount is calculated based on the difference between the actual differential and a target value for the instant set of operating conditions. The second reduction amount is also subtracted from the injection volume which is calculated based on the engine speed and a signal which is indicative of the power demand on the engine (the accelerator pedal depression degree).

Abstract: An intake manifold for a multi-cylinder internal combustion engine of the type wherein blow-by gas and/or EGR gas is supplied to engine cylinders. The intake manifold comprises a plurality of branch runners each of which has a flange section fixedly secured to a cylinder head of the engine. A rib section integrally bridges the flange sections of the adjacent branch runners and is formed therein with a gas passage through which blow-by gas or EGR gas flows. The gas passage is communicated with the intake air passages of the adjacent branch runners so that the blow-by gas or EGR gas is uniformly distributed into the adjacent branch runners.

Abstract: In a DOHC engine, a sprocket chamber is formed at the cylinder head at one end thereof, and formed with a lateral opening. A timing chain drivingly interconnects a crankshaft and an idler gear, whereas a camshaft driving chain drivingly interconnects the idler gear and a pair of cam sprockets. A first tensioner is mounted to a cylinder block for adjusting the tension of the timing chain, whereas a second tensioner is mounted to the sprocket chamber for adjusting the tension of the camshaft driving chain. There are provided means for defining an access to the first tensioner.

Abstract: A V-type engine includes first and second camshafts rotatably mounted to cylinder heads, respectively. A first chain drivingly interconnects a crankshaft and the first camshaft, whereas a second chain drivingly interconnects the crankshaft and the second camshaft. First and second tensioners provide the tensions to the first and second chains, respectively. For concealing the first and second chains, the engine has a cover formed with two openings positioned in accordance with the first and second tensioners.