Abstract: A method for warning of insufficient engine oil for a vehicle includes: determining, by a controller, whether conditions for determining that the vehicle has insufficient engine oil are satisfied, after an engine of the vehicle is started; determining, by the controller, whether an integrated value obtained by integrating a difference between a target operating value and an actual operating value of a hydraulic continuously variable valve timing (CVVT) device included in the engine within an operating time period of the hydraulic CVVT device is equal to or greater than a reference difference value, when the conditions for determining whether the vehicle has insufficient engine oil are satisfied; and determining, by the controller, that the vehicle has insufficient engine oil based on counting information on the number of times the integrated value, obtained by integrating the difference between the target operating value and the actual operating value, is equal to or greater than the reference difference valu

Abstract: A method for warning of insufficient engine oil for a vehicle includes: determining, by a controller, whether conditions for determining that the vehicle has insufficient engine oil are satisfied, after an engine of the vehicle is started; determining, by the controller, whether an integrated value obtained by integrating a difference between a target operating value and an actual operating value of a hydraulic continuously variable valve timing (CVVT) device included in the engine within an operating time period of the hydraulic CVVT device is equal to or greater than a reference difference value, when the conditions for determining whether the vehicle has insufficient engine oil are satisfied; and determining, by the controller, that the vehicle has insufficient engine oil based on counting information on the number of times the integrated value, obtained by integrating the difference between the target operating value and the actual operating value, is equal to or greater than the reference difference valu

Abstract: A system for inhibiting seizure of a bearing may include: a knocking sensor provided at one side of an engine to measure vibration transmitted from the engine and detect knocking of the engine, and a controller for controlling operation of the engine. In particular, the controller determines that a bearing of the engine is damaged when a magnitude of vibration of the engine inputted from the knocking sensor is greater than a damaged-bearing judging threshold value while the engine is operated in a damaged-bearing detecting region which is a region where knocking does not occur.

Abstract: A system for inhibiting seizure of a bearing may include: a knocking sensor provided at one side of an engine to measure vibration transmitted from the engine and detect knocking of the engine, and a controller for controlling operation of the engine. In particular, the controller determines that a bearing of the engine is damaged when a magnitude of vibration of the engine inputted from the knocking sensor is greater than a damaged-bearing judging threshold value while the engine is operated in a damaged-bearing detecting region which is a region where knocking does not occur.

Abstract: A method of preventing bearing seizure may include using at least one of a knock sensor, an engine oil pressure sensor, and a continuously variable valve timing (CVVT) system as a bearing seizure detection factor by a bearing controller, detecting damage of a bearing applied to an engine during operation of the engine in which a state of the bearing seizure detection factor is changed, and performing engine control using the bearing seizure detection factor when the bearing damage is detected.

Abstract: A method of preventing bearing seizure may include using each of a knock sensor, an engine oil pressure sensor, and a continuously variable valve timing (CVVT) system as a bearing seizure detection factor by a bearing controller, detecting damage of a bearing applied to an engine during operation of the engine in which a state of the bearing seizure detection factor is changed, and performing engine control using the bearing seizure detection factor when the bearing damage is detected.

Abstract: A method for controlling engine knocking, in which a retarded timing is recovered based on a retarded timing amount learned when the engine knocking occurs during driving of a vehicle, includes a first process of retarding an ignition timing based on the previously learned retarded timing amount in a reference engine operating condition entered during driving of the vehicle. A second process recovers the retarded timing when a first condition in which a time duration acquired by accumulating a driving time under the reference engine operating condition is equal to or more than a reference time duration and a second condition in which the engine knocking does not occur while driving under the reference engine operating condition are satisfied.

Abstract: A method for controlling engine knocking, in which a retarded timing is recovered based on a retarded timing amount learned when the engine knocking occurs during driving of a vehicle, includes a first process of retarding an ignition timing based on the previously learned retarded timing amount in a reference engine operating condition entered during driving of the vehicle. A second process recovers the retarded timing when a first condition in which a time duration acquired by accumulating a driving time under the reference engine operating condition is equal to or more than a reference time duration and a second condition in which the engine knocking does not occur while driving under the reference engine operating condition are satisfied.

Abstract: A method of monitoring an EGR system includes setting up an ignition timing map depending on EGR efficiency when the EGR system operates normally. An output value reflecting the driving state of a vehicle is divided into an active area and an inactive area. A detected value of ignition timing depending on the occurrence of knocking for the active and inactive areas is learned and stored. When knocking occurs in the active area, a corrected value of ignition timing influenced by only the operation of the EGR system is extracted using the difference between the detected values of ignition timing learned in the active and inactive areas. The amount of variation in the EGR efficiency influenced by the operation of the EGR system is measured by measuring the EGR efficiency by applying the corrected value of ignition timing to the ignition timing map.

Abstract: A knocking control method based on a separation learning range may include (a) designating a learning cell in a driving range represented by a load-rotating number, (b) dividing the learning cell into individual cells, (c) designating a knocking cell of a partial load and a knocking cell of a full load, respectively, as other cells; and (d) determining a reference of a spark timing advanced and lagged angle by a difference between a partial load learning value of a high load and a learning value in the full load and based on the determined reference, simultaneously performing a knocking cell learning of the partial load and a knocking cell learning of the full load or not performing the knocking cell learning of the full load at the time of performing the knocking cell learning of the partial load.

Abstract: A method of monitoring an EGR system includes setting up an ignition timing map depending on EGR efficiency when the EGR system operates normally. An output value reflecting the driving state of a vehicle is divided into an active area and an inactive area. A detected value of ignition timing depending on the occurrence of knocking for the active and inactive areas is learned and stored. When knocking occurs in the active area, a corrected value of ignition timing influenced by only the operation of the EGR system is extracted using the difference between the detected values of ignition timing learned in the active and inactive areas. The amount of variation in the EGR efficiency influenced by the operation of the EGR system is measured by measuring the EGR efficiency by applying the corrected value of ignition timing to the ignition timing map.

Abstract: An exhaust pipe structure of a vehicle having a left manifold disposed in front of an engine and a right manifold disposed behind the engine along a longitudinal direction of the vehicle, which are connected by an underbody catalytic converter, the exhaust pipe structure may include a left exhaust pipe connected to the left manifold and extending toward the rear of the engine, a right exhaust pipe having a straight portion connected to the right manifold and extending toward the front of the engine and a curved portion bending from the straight portion toward the rear of the engine, and a conjunction, one end of which is connected to and communicates with the end of the curved portion of the right exhaust pipe and the end of the left exhaust pipe and the other end of which is connected to the underbody catalytic converter.

Abstract: An intake/exhaust valve for a vehicle to prevent the valve from fixation (valve absorption) may include a first valve stem body which is extruded from a valve head, has a first diameter and is a portion where a relative motion of a valve stem occurs; and a second valve stem body which is formed above the first valve stem body and has a second diameter. The second diameter is less than the first diameter. The relative clearance between the first valve stem body and a valve guide is predetermined for stable guiding of a valve closing, and the relative clearance between the second valve stem body and the valve guide is predetermined for preventing carbon fixation.

Abstract: The present invention relates to an intake manifold for a vehicle and comprises tanks for stabilizing intaken air introduced from a throttle body; a plurality of zip tubes diverged from the tanks; a plurality of runners connected to the zip tubes and communicated with respective cylinders; and a adjustment apparatus provided at one side of the zip tubes and the runners for varying the diameter of the zip tube and the diameter of the runner according to an engine operation range. Due to the above structure, the diameter of the zip tube and the diameter of the runner can be varied continuously within the overall operating range of an engine by the adjustment apparatus. Hence, the performance of the engine can be enhanced.

Abstract: An exhaust pipe structure of a vehicle having a left manifold disposed in front of an engine and a right manifold disposed behind the engine along a longitudinal direction of the vehicle, which are connected by an underbody catalytic converter, the exhaust pipe structure may include a left exhaust pipe connected to the left manifold and extending toward the rear of the engine, a right exhaust pipe having a straight portion connected to the right manifold and extending toward the front of the engine and a curved portion bending from the straight portion toward the rear of the engine, and a conjunction, one end of which is connected to and communicates with the end of the curved portion of the right exhaust pipe and the end of the left exhaust pipe and the other end of which is connected to the underbody catalytic converter.

Abstract: A variable intake system may include intake runners that are respectively connected to a plurality of cylinders to supply air that flows therein to the cylinders, a plenum, one side of which is connected to the intake runners and distributes the air to the intake runners, a first resonance pipe, one end of which is connected to the other side of the plenum to supply the air therein, a second resonance pipe, one end of which is connected to the other side of the plenum to supply the air therein, the length thereof being shorter than that of the first resonance pipe and the cross-section thereof being wider than that of the first resonance pipe, and a junction pipe connected to the other ends of the first and second resonance pipes and supplying the air to the first and second resonance pipes respectively from an intake line.

Abstract: The present invention relates to an intake manifold for a vehicle and comprises tanks for stabilizing intaken air introduced from a throttle body; a plurality of zip tubes diverged from the tanks; a plurality of runners connected to the zip tubes and communicated with respective cylinders; and a adjustment apparatus provided at one side of the zip tubes and the runners for varying the diameter of the zip tube and the diameter of the runner according to an engine operation range. Due to the above structure, the diameter of the zip tube and the diameter of the runner can be varied continuously within the overall operating range of an engine by the adjustment apparatus. Hence, the performance of the engine can be enhanced.

Abstract: A pressure adjusting valve for a vehicle fuel line includes a diaphragm disposed in a housing and dividing the interior of the housing into first and second compartments. A valve plate is provided in the second compartment and attached to the diaphragm. A return unit is provided in the second compartment. An elastic member provides an elastic force to the diaphragm toward the second compartment. An elastic force adjusting unit controls the elastic force of the elastic member.