Abstract: The present invention is a dual-stage fuel injection strategy for compression ignition engines in which 15-40% of the fuel is injected into the combustion chamber no later than about −20 to −30 CA ATDC and as early as IVC. The rest of the fuel is then injected in one or more fuel pulses, none of which start before about −20 to −30 CA ATDC. The fuel injected early in the compression stroke forms a lean mixture that burns with low soot and low NOx emissions. The combustion of that fuel serves to increase in-cylinder temperature such that the ignition delay of subsequent fuel injection pulses is short. This mode is utilized when it is predicted that a NOx spike is imminent. Various other alternative methods for reducing NOx spikes are also disclosed such as specialized EGR systems that can provide EGR with low manifold vacuum.

Abstract: A processing apparatus is powered by an internal combustion engine. Airborne emissions that are separate from the exhaust of the internal combustion engine are produced during processing. An air feedback mechanism directs the airborne emissions produced during processing to the air intake of the internal combustion engine, resulting in the emissions being combusted within a combustion area in the internal combustion engine. By combusting the emissions, the harmful level of emissions is reduced.

Abstract: A fuel injection control system for an internal combustion engine is capable of expanding a correction allowable range employed in correcting a fuel injection quantity when refueling is detected. The fuel injection control system estimates a fuel property of fuel injected into the internal combustion engine after the correction allowable range is expanded and sets the correction allowable range on the basis of the estimated fuel property.

Abstract: A fuel injector (5) injects fuel to generate an air-fuel mixture that is burnt in the engine (1), and a sensor (16) detects an air-fuel ratio of the air-fuel mixture from an exhaust gas composition of the engine (1). A controller (11) calculates a dead time representing a lag between the air-fuel ratio variation of the air-fuel mixture and the air-fuel ratio variation detected by the sensor (16), and calculates an estimated state quantity by applying a dead time compensation according to Smith method and a disturbance compensation to the air-fuel ratio detected by the sensor (16). By determining an air-fuel ratio feedback correction amount based on the estimated state quantity applying a sliding mode control process, the response and stability of air-fuel ratio control is improved.

Abstract: A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.

Abstract: A method and associated arrangement for achieving an adjusted engine setting utilizing engine output and/or fuel consumption. An engine that consumes fuel is run. Fuel consumption and/or engine operation output is determined. A value is determined utilizing the determined fuel consumption and/or the determined engine operation output. The engine setting is adjusted to cause the determined value to change toward a desired value.

Abstract: A method of metering fuel with a fuel injector, in particular a fuel injector for fuel injection systems in internal combustion engines is described, having a piezoelectric or magnetostrictive actuator and a valve closing body which is operable by the actuator with a valve lift, cooperating with a valve seat face provided on a valve seat body to form a sealing seat. The valve lift may be adjusted variably as a function of a variable control signal triggering an actuator to produce a variable fuel flow at the sealing seat. To produce afitted curve, the fuel flow of the fuel jet sprayed by the fuel injector is measured as a function of the control signal to produce a fitted curve, and a predetermined fuel flow is set with the control signal by using the fitted curve.

Abstract: An air-fuel ratio control apparatus for an internal combustion engine in which an air-fuel ratio is always controlled to be a target value with accuracy when purge air is introduced is obtained.

Abstract: A collecting exhaust port 18 provided in a cylinder head 12 is comprised of exhaust port sections 46 extending from exhaust valve bores 35 in cylinders 14, and an exhaust collecting section 47 in which the exhaust port sections 46 are collected. The cylinder head 12 includes a protrusion 49 projecting in an arch shape outside a side wall 111 of a cylinder block 11. The exhaust collecting section 47 of the collecting exhaust port 18 directly faces an inner surface of a side wall 12 of the protrusion 49. Water jackets J2 and J3 for cooling the protrusion 49 are provided in upper and lower surfaces of the protrusion 49 having the collecting exhaust port 18 defined therein. The water jackets J2 and J3 are not provided between the side wall 121 of the protrusion 49 and the exhaust collecting section 47. Thus, the compact cylinder head 12 having the collecting exhaust port 18 integrally provided therein can be formed, while avoiding the complication of the structure of a core.

Abstract: A process and a device for controlling selective cylinder filling in combustion engines with a variable valve drive, where the valve stroke and/or the valve opening and closing times of the cylinder intake valves are controllable. In order to ensure satisfactory idling quality also in direct fuel-injection engines in spite of the occurring production tolerances, at least one input magnitude is determined on whose basis conclusions can be drawn as to the filling level or filling level differences of each cylinder. From this input magnitude, a control signal for the variable valve operation is determined such that differing filling levels of the cylinder can be balanced out by adjusting the valve drive.

Abstract: A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.

Abstract: A generic technique for the detection of air-fuel ratio or torque imbalances in a three-cylinder engine equipped with either a current production oxygen sensor or a wide-range A/F sensor, or a crankshaft torque sensor, is disclosed. The method is based on a frequency-domain characterization of pattern of imbalances and its geometric decomposition into two basic templates. Once the contribution of each basic template to the overall imbalances is computed, templates of same magnitude of imbalances but of opposite direction are imposed to restore air-fuel ratio (or torque) balance among cylinders. At any desired operating condition, elimination of imbalances is achieved within few engine cycles. The method is applicable to current and future engine technologies with variable valve-actuation, fuel injectors and/or individual spark control.

Abstract: A method for operating an electronic controller of a motor vehicle, in particular of an engine controller, with which signal processing is carried out in order to control the operation of the motor vehicle and/or of the engine. The signal processing of the controller includes a filtering operation, the filtering operation being carried out as a function of the operating state of the motor vehicle and/or of the engine.

Abstract: A state quantity &sgr;(n) of a switching function is calculated based on a predetermined target air-fuel ratio TGABF, a detected air-fuel ratio AFSAF detected by a sensor (16), and a state equation derived from a transfer function Geng(q) of a secondary discrete system, representing the correlation between an air-fuel ratio of an air fuel mixture in a combustion chamber (1A) and the detected air-fuel ratio (S14). The air-fuel ratio is feedback corrected by applying a sliding mode control process based on the difference between the target air-fuel ratio TGABF and the detected air-fuel ratio AFSAF, and the state quantity &sgr;(n) (S14-S21). The response and robustness of the air-fuel ratio control are enhanced by using a physical model of the secondary discrete system.

Abstract: An engine controller regulates fuel flow to an internal combustion engine based on sensed air flow and sensed engine operational parameters. The engine controller includes a speed sensor, a power sensor, an airflow meter and a controller unit. The speed sensor generates an engine speed signal representative of sensed engine speed, the power sensor generates an output power signal representative of sensed engine output power and the airflow meter generates an actual airflow signal representative of sensed airflow. The controller unit is responsive to the engine speed signal, the output power signal and the actual airflow signal and develops a command signal for an air-fuel mixer.

Abstract: A fuel supply system 10 for an internal combustion engine includes a housing 12 defining a chamber 14 and provided with an inlet opening 16 upstream of the chamber 14 and an outlet opening 18 downstream of the chamber 14. The fuel injector 20 sprays a fuel mist into the chamber 14. A heater 22 heats air flowing into the chamber 14 via inlet 16 to a temperature of between 110° C.-260° C. Pressure within the chamber 14 is also negative relative to ambient pressure. The fuel sprayed into the chamber 14 via the fuel injector 20 is thermally cracked so that a mixture of thermally cracked fuel and heated air flows out from the outlet 18 for combustion in combustion chambers of the engine.

Abstract: A watercraft incorporates a multiple cylinder engine and an exhaust system that guides exhaust gases from the engine to an external location. An oxygen sensor is provided to detect a residual amount of exhaust gases. An engine body of the engine defines a plurality of inner exhaust passages that communicate with respective combustion chambers. The exhaust system incorporates an exhaust conduit such as an exhaust manifold that defines individual exhaust passages therein that communicate with the respective inner exhaust passages. The oxygen sensor is positioned either at one of the inner exhaust passages or at one of the individual exhaust passages.

Abstract: For a control model which simulates a control object ranging from the fuel injection valve up to the air-fuel ratio sensor, coefficients of a characteristic polynomial of the control model are calculated based on the pole arrangement scheme, with roots equal in number to the dead time of the control model being made 0, control parameters are calculated from the coefficients of the characteristic polynomial and from model parameters, and the air-fuel ratio correction factor is calculated from the control parameters. The control model is expressed in terms of a dead time plus first-order lag system, with the total number of roots being set greater by two than the number n of roots which are derived from the time lag, and unknown roots other than those of the dead time are solved based on formulas which are expressed in terms of a second-order lag system.

Abstract: A fuel injection control system for an internal combustion engine is capable of expanding a correction allowable range employed in correcting a fuel injection quantity when refueling is detected. The fuel injection control system estimates a fuel property of fuel injected into the internal combustion engine after the correction allowable range is expanded and sets the correction allowable range on the basis of the estimated fuel property.

Abstract: A state quantity &sgr;(n) of a switching function is calculated based on a predetermined target air-fuel ratio TGABF, a detected air-fuel ratio AFSAF detected by a sensor (16), and a state equation derived from a transfer function Geng(q) of a secondary discrete system, representing the correlation between an air-fuel ratio of an air fuel mixture in a combustion chamber (1A) and the detected air-fuel ratio (S14). The air-fuel ratio is feedback corrected by applying a sliding mode control process based on the difference between the target air-fuel ratio TGABF and the detected air-fuel ratio AFSAF, and the state quantity &sgr;(n) (S14-S21). The response and robustness of the air-fuel ratio control are enhanced by using a physical model of the secondary discrete system.

Abstract: An engine oxygen concentration sensor mounting structure in which an oxygen concentration sensor is mounted in an exhaust pipe connected to an outlet of an exhaust manifold having a plurality of exhaust single pipes. When a straight line is drawn from a detection part of the oxygen concentration sensor positioned within the exhaust pipe so as to be parallel to a section of a centerline of the exhaust pipe closest to the detection part, the straight line passes outside the outlet of the exhaust manifold. This allows the exhaust gases discharged from the exhaust manifold to be sufficiently mixed within the curved exhaust pipe and differences in length of the plurality of the exhaust single pipes to be compensated for. Thus, accurate detection by the oxygen concentration sensor can be secured, even if the lengths of a plurality of exhaust single pipes of the exhaust manifold are nonuniform.

Abstract: The air-fuel ratio of an air-fuel mixture to be combusted in an internal combustion engine 1 is manipulated to converge an output VO2/out of an O2 sensor 6 which is disposed downstream of a catalytic converter 3 to a target value VO2/TARGET depending on an operating state of the internal combustion engine 1, while at the same time a deterioration evaluating parameter is determined from time-series data of the output VO2/out of the O2 sensor 6. The value of the deterioration evaluating parameter is corrected depending on an average value of the output VO2/out of the O2 sensor 6 or the target value VO2/TARGET, and the deteriorated state of the catalytic converter 3 is evaluated based on the corrected value of the deterioration evaluating parameter.

Abstract: A catalyst which has an oxygen storage function is provided in the exhaust gas pipe 2 of an engine 1. The oxygen storage amount is estimated based on the output of the air/fuel ratio sensor 4 upstream of the catalyst 3. The air/fuel ratio is controlled so that the oxygen storage amount coincides with the target value. When the output of the downstream air/fuel ratio sensor 5 continuously displays a rich or a lean value for more than a determination time which is varied continuously with respect to operating conditions, deterioration in the upstream air/fuel ratio sensor 4 is detected. Thus the output of the upstream air/fuel ratio sensor 4 is corrected based on the output of the downstream air/fuel ratio sensor 5. In this manner, output fluctuations are corrected based on the deterioration of the air/fuel ratio sensor 4 upstream of the catalyst.

Abstract: An equivalence ratio-based system for controlling transient engine fueling includes an engine controller responsive to a number of engine operating conditions to estimate a mass of oxygen trapped within a number of cylinders of an internal combustion engine. The engine controller is further operable to map current values of engine speed and commanded fueling to one of a number of predetermined maximum fuel-to-oxygen, or equivalence, ratio values (&PHgr;MAX). The engine controller is then operable to determine an oxygen/fuel control (OFC) limited fueling command (FOFCL) as a function of the estimated oxygen mass value and the maximum equivalence ratio, and to limit engine fueling based on the OFC limited fueling command FOFCL. In one embodiment, the engine controller is operable to fuel the engine according to a minimum of the OFC limited fueling command FOFCL and a default fueling command FDEF, although other fuel limiting strategies are contemplated.

Abstract: A fuel supply for an internal combustion engine includes providing a source of a first fluid fuel and a source of a second fluid fuel which are separate from one another, sensing at least one operational parameter of an internal combustion engine, supplying the first fuel from the one source and the second fuel from the other source in quantities which are determined in correspondence with the sensed operational parameter of the internal combustion engine, and mixing the first fuel and the second fuel in with the quantities determined in correspondence with the sensed operational parameter so as to produce a fuel mixture to be supplied to the internal combustion engine.

Abstract: A method and apparatus controls an internal combustion engine of a vehicle in which an exhaust purifying catalyst capable of storing oxygen is provided in an exhaust system of the engine. The internal combustion engine is adapted to be temporarily stopped when a predetermined condition for stopping the engine is satisfied, and resumes its operation when the predetermined condition is eliminated. The internal combustion engine is operated so as to reduce an amount of oxygen stored in the exhaust purifying catalyst during a temporary stoppage of the engine, before fuel starts being burned for resuming the operation of the engine.

Abstract: In a multi cylinder internal combustion engine comprising a cylinder head internally defining exhaust passages extending from a plurality of combustion chambers defined in part by the cylinder head, the exhaust passages converging into a converging area also internally defined in the cylinder head, an oxygen sensor for detecting an oxygen concentration in exhaust gas is passed into the converging area substantially in parallel with a cylinder axial line. Thus, the oxygen sensor can be mounted relatively close to the combustion chamber while permitting the sensor to be uniformly exposed to the exhaust gas from the combustion chambers of an entire cylinder bank. Therefore, the oxygen sensor can be activated relatively quickly substantially without any warm-up, and can measure the oxygen concentration of the overall exhaust gas.

Abstract: An equivalence ratio-based system for controlling transient engine fueling includes an engine controller responsive to a number of engine operating conditions to estimate a mass of oxygen trapped within a number of cylinders of an internal combustion engine. The engine controller is further operable to map current values of engine speed and commanded fueling to one of a number of predetermined maximum fuel-to-oxygen, or equivalence, ratio values (&PHgr;MAX). The engine controller is then operable to determine an oxygen/fuel control (OFC) limited fueling command (FOFCL) as a function of the estimated oxygen mass value and the maximum equivalence ratio, and to limit engine fueling based on the OFC limited fueling command FOFCL. In one embodiment, the engine controller is operable to fuel the engine according to a minimum of the OFC limited fueling command FOFCL and a default fueling command FDEF, although other fuel limiting strategies are contemplated.

Abstract: A sensor for determining an oxygen content in an exhaust gas of an internal combustion engine includes a receptacle, arranged in a longitudinal bore of a metal housing, for a sensing element. The sensing element is received in the receptacle in a gas-tight fashion via a sensing element seal, which includes a glass seal. The receptacle has a measured-gas-side ceramic shaped element and a connector-side ceramic shaped element, which are arranged axially one behind the other. A cavity into which the glass seal is pressed while hot is configured between the two ceramic shaped elements.

Abstract: The invention relates to an internal combustion engine, comprising a cylinder block with at least one cylinder barrel, a cylinder head with at least one inlet channel and exhaust channel with related inlet and exhaust valves to a combustion chamber situated above a piston moveable in the cylinder barrel and a crank case for lubricating oil situated below the piston, wherein the piston has at least two grooves situated at a distance from each other, each having a piston ring and a piston collection chamber contained between the rings. The engine has an expansion chamber commonly connected to each cylinder barrel via an individual evacuation port, said port opening out into the respective cylinder barrel, the expansion chamber forming a communicating connection between the cylinder barrel and the inlet channel via the evacuation port and an evacuation channel, said evacuation channel opening out into at least one inlet channel or inlet manifold.

Abstract: A circuit for improving the resolution of an oxygen sensor in a vehicle exhaust system. The circuit expands a limited output voltage range of an oxygen sensor to full voltage range of an analog-to-digital (A/D) converter, prior to input of the expanded signal into the A/D converter. Utilization of the full range of converter provides improved resolution for analyzing the analog signal.

Abstract: An engine control system includes an adaptive bias sub-system (100) that generates bias values for controlling the air-fuel ratio. The sub-system (100) includes an integral controller (118) that reads an error signal from a post-catalyst switching EGO sensor (112). A plurality of noise isolation integrators (122) filter any noise resulting from a particular engine operating condition (e.g. acceleration, deceleration, idling) from the integrated error signal and stores the signal in a corresponding keep-alive memory (124) as a bias value for that engine operating condition. In a preferred embodiment, the post-catalyst feedback loop includes a gated proportional controller 116 that turns on for a limited period of time after the post-catalyst switching EGO sensor (112) switches states.

Abstract: An engine control system of an internal combustion engine coupled to a NOx trap uses a measured air-fuel ratio downstream of the NOx trap to control engine air-fuel ratio. The measured air-fuel is only used for feedback when it indicates a value away from stoichiometry. Thus, NOx and oxygen storage effects that cause inlet air-fuel ratio to be different from exit air-fuel ratio do not cause degraded feedback air-fuel ratio control.

Abstract: An air-fuel ratio control apparatus performs an intake air-increasing process based on a region of an air-fuel ratio feedback adjustment coefficient FAF in which the adjustment coefficient decreases the fuel concentration in an air-fuel mixture. The apparatus calculates a fuel injection valve open duration TAU by using a newly calculated air-fuel ratio feedback adjustment coefficient FAFx, instead of using an adjustment coefficient FAF. An air-fuel ratio-increasing feedback adjustment coefficient FVLV in the adjustment coefficient FAFx has a value that cancels an increase in the amount of intake air. Therefore, the fuel injection amount is increased only when the fuel concentration in the mixture is an intake air-increasing process. Hence, torque difference between fuel concentration-increasing and concentration-decreasing control becomes smaller.

Abstract: In a single-cylinder 4-cycle engine including an oxygen concentration sensor provided at a location upstream of an exhaust emission control catalyst, the influence of pulsation of the exhaust gas is eliminated to enhance the detection accuracy by detecting of the concentration of oxygen in the exhaust gas. A first pulse generator generates a pair of pulse signals a and b per one rotation of a crankshaft, and a second pulse generator generates pulse signals c and d at every very small angle of rotation of the crankshaft. The angular speed of the crankshaft is detected from the interval of the pulse signals c and d. The pulse signal output a when the angular speed is smaller is determined as being the output during a compression stroke, and is used as an ignition signal a1. The pulse signal output a when the angular speed is larger is determined as being the output during an exhaust stroke, and is used as an oxygen concentration detecting signal a2.

Abstract: A control method for controlling injection of an engine having an oxygen concentration sensor generating a composition signal as a function of the oxygen difference in the exhaust gases with respect to the stoichiometric condition of the burnt air/fuel mixture, and a number of injectors for injecting fuel for an operating injection time in each operating state of the engine, and each of which is assigned, in each operating state of the engine, a respective calibration injection time determined at an initial engine calibration stage using a reference fuel.

Abstract: An engine control system for a direct injection-spark ignition type of engine which is equipped with a fuel injector for spraying fuel directly into a combustion chamber, an exhaust system having a lean NOx conversion catalyst for lowering an emission level of nitrogen oxides (NOx) in exhaust gas and an exhaust gas recirculation system divides a given amount of fuel into two parts which are intermittently delivered through early and late split injection respectively in a intake stroke and controls a fuel injector such that a midpoint between points at which the early and late split injection are timed respectively to start is before a midpoint of a intake stroke and the exhaust gas recirculation system admits exhaust gas partly into an intake air stream while the engine is in a lean homogeneous charge zone.

Abstract: A sensor for determining an oxygen content of an exhaust gas of an internal combustion engine includes a flat-plate sensing element that is inserted in a gas-tight fashion via a hybrid seal in a ceramic shaped element that is arranged in a metal housing. The seal includes a powdered sealing packing, both placed around the sensing element in a recess at one end of the ceramic shaped element and a fusible glass seal located above the powdered sealing packing. The seal achieves gas-tight and gasoline-resistant isolation or immobilization of the sensing element in the ceramic shaped element.

Abstract: The apparatus includes a sensor capable of delivering a voltage representative of the ratio between a reference oxygen pressure and the oxygen pressure in a volume of the sensor and provided with electrodes (12, 14) via which it is possible to pass a pumping current that controls said oxygen pressure in the volume, and monitoring and control means including a digital controller (26) receiving said representative voltage on an input and suitable for delivering the pumping current. The monitoring and control means deliver the pumping current in the form of a current that varies continuously and progressively, without interruptions, governed by the digital controller in such a manner as to servo-control the input voltage to a determined value.

Abstract: A gaseous-fueled reciprocating internal combustion engine includes a carburetor having a throttle valve that is controlled by a speed governor. A proportional fuel control valve is disposed intermediate a fuel supply and the carburetor, and is controlled by an air fuel computing device. The computing device generates a control signal to adjust the fuel control valve based on a governor sensed variable indicative of engine speed, sensed engine torque, a governor output signal from the governor indicative of an opening position of the throttle valve wherein 100% corresponds to a wide open throttle position, and 0% corresponds to a closed position, and a lean combustion control map containing predetermined set point values stored in memory.

Abstract: A feed back control system for a direct injected, two cycle engine having a catalytic exhaust. The injection control is modified if the catalyst overheats to control its temperature.

Abstract: An engine exhaust gas purification system having a catalyst in an exhaust system of the engine, said catalyst reducing nitrogen oxide when exhaust gas generated by the engine is in an oxidizing state. In the system, engine operating parameters, including at least an engine speed and an engine load, are determined and catalyst temperature is determined, and air/fuel ratio is controlled in response to the detected parameters and the determined catalyst temperature, thereby enabling the catalyst to purify NOx in its optimum temperature characteristic range to achieve enhanced NOx constituent purification performance in an oxidizing environment. Alternatively, the air/fuel ratio is controlled in the stoichiometric or richer direction when the catalyst temperature is high, thereby protecting the catalyst from being damaged. The catalyst is a selective-reduction type nitrogen oxide reduction catalyst.

Abstract: A feed back control system and method for direct injected engines, particularly useful in marine applications to avoid excessive hunting due to the close proximity of the sensor to the fuel injector. Both injection initiation and duration are controlled. Under certain conditions such as lean burn, steady state and transition from rich to lean the control is initially of only one of these two factors. If the air fuel ratio is then still out of range, the other control is effected.

Abstract: A method for adjusting a fuel control system of an internal combustion engine to account for variations in the energy content of a fuel delivered to the engine involves monitoring the O.sub.2 level of the engine exhaust gases. The fuel may be a gaseous fuel for example. The fuel control system utilizes a stored gaseous fuel energy content value (E.sub.G) to determine the necessary duration of a gaseous fuel admission valve control signal. The method includes sensing an actual engine exhaust gas O.sub.2 level and comparing the actual exhaust gas O.sub.2 level with a desired exhaust gas O.sub.2 level. The stored gaseous fuel energy content value (E.sub.G) is adjusted based upon the comparison. The desired exhaust gas O.sub.2 level may be determined as a function of one or more engine operating parameters which indicate a desired or expected air/fuel ratio, the level of O.sub.2 in the exhaust gases being an indicator of the air/fuel ratio.

Abstract: A control system for an outboard motor is disclosed. The control system includes a feedback control which obtains feedback data from a combustion condition sensor. The motor includes an engine positioned in a cowling and having a vertically extending output shaft in driving relation with a water propulsion device of the motor. The engine has at least one combustion chamber and an air/fuel charging system for delivering air and fuel into the combustion chamber for combustion therein. The motor includes an exhaust system for routing exhaust from the engine to a point external to the motor. The exhaust system includes an exhaust passage leading from the chamber to a main exhaust passage which extends vertically downward to an exhaust guide positioned below the engine. A passage leads from the exhaust guide into an expansion chamber and thereon to an exhaust discharge.

Abstract: An air/fuel control system (8) and method for an engine (28) having two engine banks coupled to a single catalytic converter (50) uses first and second exhaust gas oxygen sensors (44, 55) coupled to respective first and second exhaust manifolds (56, 57) and various engine operating parameters. During a first set of engine operating conditions, air/fuel control system (8) maintains the exhaust air/fuel ratio oscillations of the two bank in phase with one another. During a second set of engine operating conditions, air/fuel control system (8) maintains the exhaust air/fuel ratio oscillations of the two bank 180 degrees out of phase with one another. When transitioning, emission impacts are minimized.

Abstract: In an engine fuel supply system, the difference between the actual and target air-fuel ratios, an air-fuel ratio feedback correction coefficient and a learned correction amount are added as a parameter for diagnosing the fuel supply system. The diagnostic parameter is smoothed and the smoothed value is compared with a diagnosis reference value, thereby detecting a malfunction in the fuel supply system. Even if the learned correction amount is not updated, the malfunction in the fuel supply system can be promptly detected from the difference between the actual and target air-fuel ratios and the air-fuel ratio correction coefficient. The diagnosis reference value is determined variably in accordance with engine operating parameters such as the amount of intake air.

Abstract: A two-cycle crankcase compression, direct injected internal combustion engine having several embodiments of feedback control systems. In each embodiment, the feedback control system includes at least one combustion condition sensor such as an oxygen sensor. The sensor is mounted, however, so that it communicates with the combustion gases through a sensor port that is disposed so that it will not receive fuel sprayed from the fuel injector. In one embodiment, the sensor port is positioned in a common portion of an exhaust manifold upstream of an exhaust control valve. In another embodiment, the sensor port is disposed directly in the cylinder but adjacent the injector so that the spray from the injector will be away from the sensor port.

Abstract: A method of determining a mass of fuel to be introduced into a suction pipe or into a cylinder of an internal combustion engine precontrols a basic injection time constituting a basic injection quantity, through a prescription of a lambda set point. The lambda set point is determined by a coordinated calculation through selecting a minimum and a maximum from a multiplicity of different lambda requirements which are derived from operating states of the internal combustion engine. Different priorities are allocated to the various lambda requirements.

Abstract: This device applies to all internal combustion heat engines. It includes an electronic unit (10) associated with a ring gear (12) of the inertial flywheel and with sensor (22) with variable reluctance such as those used for electronic ignition engines. Instantaneous period d.sub.i of advancement of teeth (14-16) is produced (26-30-32-34). From signal d.sub.i, period T.sub.4 of the fraction of revolution of the flywheel corresponding to a period of the combustions is calculated (36) and stored (38). A magnitude D'.sub.4, representative of a projection of the alternating component of the angular velocity of the flywheel at the frequency of the combustions is also calculated (40-42). A calculating stage (44) combines (T.sub.4 and D'.sub.4) with constants A and B suited to the type of engine for producing signals for measuring the average gas torque for each combustion of the gas mixture in the cylinders of the engine.