Abstract: A control method for a spark-ignited internal combustion engine includes generating plasma by interacting an electric field generated in a combustion chamber by electric field generation means with spark discharge caused by a spark plug, and igniting an air-fuel mixture, wherein the electric field generated by the electric field generation means is set to an intensity weaker than that of an electric field generated by the spark plug when the spark discharge is caused, and set to an intensity at which discharge into the combustion chamber is disabled, and the air-fuel mixture can be securely ignited and combusted at an intended ignition timing and at a position of the spark plug.

Abstract: A diesel engine includes: a PM filter provided in its exhaust passage; a fuel injection valve for performing post fuel injection in a cylinder of an engine body in addition to primary fuel injection, in order to supply fuel to the PM filter, to maintain its purification performance; an oil level sensor for detecting a degree of dilution of engine oil; and a first indicator lamp that is turned on to indicate that the engine oil needs to be changed when the degree of dilution of engine oil detected by the oil level sensor is equal to or greater than an allowable level. The vehicle diesel engine overrides the prohibition of the post fuel injection until a distance traveled by the vehicle after the indicator lamp is turned on reaches a predetermined distance.

Abstract: An abnormality detection apparatus for detecting an abnormality of an oil level sensor having lower and upper oil level detectors includes: a recording portion that records the output of the upper oil level detector before the internal combustion engine is started; and a determining portion that determines that the upper oil level detector has an abnormality if the output of the lower oil level detector is indicating, after the start of the internal combustion engine, that the oil level is higher than the first reference oil level while the output of the upper oil level detector recorded by the recording portion is indicating that the oil level was lower than the second reference oil level before the start of the internal combustion engine.

Abstract: A diesel engine includes: a PM filter provided in its exhaust passage; a fuel injection valve for performing post fuel injection in a cylinder of an engine body in addition to primary fuel injection, in order to supply fuel to the PM filter, to maintain its purification performance; an oil level sensor for detecting a degree of dilution of engine oil; and a first indicator lamp that is turned on to indicate that the engine oil needs to be changed when the degree of dilution of engine oil detected by the oil level sensor is equal to or greater than an allowable level. The vehicle diesel engine overrides the prohibition of the post fuel injection until a distance traveled by the vehicle after the indicator lamp is turned on reaches a predetermined distance.

Abstract: An EGR cooler system according to the invention includes an EGR cooler cooling device that is provided in a coolant path which is separate from the path provided with an engine cooling system which cools coolant. The EGR cooler cooling devices cools the coolant to be supplied to a water-cooled EGR cooler. The EGR cooler system also includes a water pump that circulates the coolant within the coolant path; a bypass passage through which the coolant may bypass the EGR cooler cooling device or the water-cooled EGR cooler; and a flow control valve that regulates the amount of coolant flowing into the bypass based on the temperature of the coolant flowing through the coolant path.

Abstract: An abnormality detection apparatus for detecting an abnormality of an oil level sensor having lower and upper oil level detectors includes: a recording portion that records the output of the upper oil level detector before the internal combustion engine is started; and a determining portion that determines that the upper oil level detector has an abnormality if the output of the lower oil level detector is indicating, after the start of the internal combustion engine, that the oil level is higher than the first reference oil level while the output of the upper oil level detector recorded by the recording portion is indicating that the oil level was lower than the second reference oil level before the start of the internal combustion engine.

Abstract: An EGR cooler system according to the invention includes an EGR cooler cooling device the is provided in a coolant path which is separate from the path provided with an engine cooling system which cools coolant. The EGR cooler cooling devices cools the coolant to be supplied to a water-cooled EGR cooler. The EGR cooler system also includes a water pump that circulates the coolant within the coolant path; a bypass passage through which the coolant may bypass the EGR cooler cooling device or the water-coolant EGR cooler; and a flow control valve that regulates the amount of coolant flowing into the bypass passage based on the temperature of the coolant flowing through the coolant path.

Abstract: A bearing device for internal combustion engines, comprising a crankshaft of an internal combustion engine and bearings supporting the crankshaft, and wherein the crankshaft is made of steel having not been subjected to surface hardening and having a structure, which is mainly composed of pearlite having the pro-eutectoid ferrite fraction of at most 3%, and is processed to have the surface roughness Rz of at most 0.8 ?m, and wherein the bearings have an aluminum bearing alloy bonded to a back plate thereof and contain, as an alloy component thereof, at least Si particles of less than 4 mass %, whereby early abrasion and scratches of the crankshaft are suppressed to be equivalent to or less than abrasion loss and scratches of conventional DCI shafts.

Abstract: A bearing device for internal combustion engines, comprising a crankshaft of an internal combustion engine and bearings supporting the crankshaft, and wherein the crankshaft is made of steel having not been subjected to surface hardening and having a structure, which is mainly composed of pearlite having the pro-eutectoid ferrite fraction of at most 3%, and is processed to have the surface roughness Rz of at most 0.8 &mgr;m, and wherein the bearings have an aluminum bearing alloy bonded to a back plate thereof and contain, as an alloy component thereof, at least Si particles of less than 4 mass %, whereby early abrasion and scratches of the crankshaft are suppressed to be equivalent to or less than abrasion loss and scratches of conventional DCI shafts.