Abstract: A vehicle/engine acceleration rate management system includes means for determining vehicle acceleration rate and a control computer providing a fueling signal to an internal combustion engine fueling system. The control computer is responsive to a gear ratio signal indicative of one of a plurality of selectable transmission gear ratios currently engaged with the engine and a vehicle acceleration rate signal to control the vehicle acceleration rate by limiting the fueling signal whenever the vehicle acceleration rate signal exceeds a vehicle acceleration limit function. In one embodiment, such vehicle acceleration rate limiting is performed only for vehicle speeds above a threshold vehicle speed, and an identical engine acceleration rate limiting procedure is performed at vehicle speeds below the threshold vehicle speed. In either case, such acceleration rate limiting is preferably only performed under manual control of engine fueling via an accelerator pedal or the like.

Abstract: A back-up battery system is provided for use with a real-time clock of an on-board device controller. In its normal operation, the real-time clock (RTC) is powered by a primary power source, such as a vehicle battery. When the primary source is interrupted, the back-up battery system is invoked to provide back-up power to the RTC. The system includes a low voltage dry cell battery mounted within a fuse component configured for electrical engagement within the vehicle fuse block. In one embodiment, a relay is interposed between the fuse component and the RTC to make and break the back-up power circuit in response to the state of the primary power source. In another embodiment, the battery within the fuse component is replaceable, with the fuse component including a base and a removable cap. In still another embodiment, the battery within the fuse component is a rechargeable battery, and the back-up power system includes a recharging circuit operable with the primary power source.

Abstract: An internal combustion engine with an embedded control system is disclosed which includes a programmable controller operatively coupled to a nonvolatile memory and a volatile memory. The nonvolatile memory is loaded with programming instructions for the controller. In one embodiment, a portion of the programming instructions are provided in an unexecutable compressed format which are then selectively decompressed into an executable format by an executable routine loaded in another portion of the nonvolatile memory. In another aspect, a first loading program is executed by the controller to load data from external support equipment. This data includes a second loading routine. The downloaded data also includes a code substitution program which is executed to replace the first loading routine with the second loading routine.

Abstract: A system and method for the diagnosis and prognosis of cylinder power imbalance in an internal combustion engine utilizes cylinder firing times to determine a differential value indicative of the power imbalance. This differential value identifies a cylinder power imbalance condition and can be used in a one dimensional or a two dimensional analysis to predict future engine performance. In one embodiment, a trend parameter is calculated from the differential values over several test sequences at periodic mileage of the vehicle. The rate and magnitude of change or deterioration of the engine performance is indicated by the trend parameter. In another embodiment, a two dimensional trend array is evaluated using singular value decomposition to arrive at an eigenvalue transformation matrix used to obtain two trend variables related to the two principal eigenvalues at a particular engine operating hour/mileage.

Abstract: A system for controlling automatic transmission downshift points includes a control computer for electronically controlling an internal combustion engine and a transmission having at least one automatically selectable gear. The control computer is responsive to at least a throttle signal, provided by either a manually actuatable accelerator pedal or a cruise control system, to compute an engine load value, and is further responsive to either an engine speed signal or a vehicle speed signal to compute a deceleration value. The control computer is operable to compute a downshift engine RPM value based on the deceleration value and either the throttle signal or the engine load value, wherein the downshift engine RPM value is lower than a default downshift engine RPM if the deceleration value indicates a relatively slow deceleration rate and the throttle signal or the engine load value indicates high throttle or engine load.

Abstract: An apparatus for diagnosing and controlling an ignition system of an internal combustion engine includes an ignition coil controllable by an ignition control circuit, a spark voltage sensor electrically connected to the high tension side of the ignition coil secondary and an ion voltage sensor electrically connected to the low tension side of the ignition coil secondary. A computer processes the spark voltage signal by comparing the signal to a number of predefined spark voltage waveforms in memory. If the spark voltage signal matches any of the spark voltage waveforms in memory that correspond to a predefined ignition system failure mode, a corresponding error code is stored in memory. The computer is further operable to process a voltage peak of the spark voltage, wherein the voltage peak corresponds to the breakdown voltage in the spark gap of a spark plug connected to the secondary coil.

Abstract: A system and method for measuring individual cylinder power contribution by cutting out individual cylinders of a multi-cylinder engine and performing a snap-throttle test on the engine. Engine speed versus time data is collected and stored during each snap-throttle test. This data is then used to calculate the power contribution provided by each cylinder using various methods, such as a least squares analysis of the speed data or by an analysis of the kinetic energy of the test engine.

Abstract: An engine control system for a vehicle engine includes an engine control module (ECM) that enters a modified sleep mode when the vehicle key switch is turned to the "off" position. In the modified sleep mode, all non-essential operating tasks normally executed by the ECM are disabled to place the ECM in a mode of reduced power consumption. In addition, various communications interrupts are disabled, except for interrupts associated with at least one external data transmission device. During the modified sleep mode, priority for communications with the external device are highest to permit external communication to and from the ECM using the external device. In this modified sleep mode, the vehicle operator or engine technician can download or upload data to and from the ECM memory. The ECM includes a sleep mode task module that is maintained during the modified sleep mode. The sleep mode task module controls a sleep mode termination timer (SMT timer) that counts the time the ECM is in the modified sleep mode.

Abstract: A fuel cooler and coolant filter assembly for the filtering of coolant and the cooling of a fuel flow for use in connection with a cylinder head of a vehicle engine includes three primary components which are assembled to one another in a stacked configuration and which in turn are assembled to the cylinder head. These three primary components include a fuel cooler core which is assembled directly to the cylinder head and which includes a fuel inlet, a fuel outlet, and a heat exchanger. The interior of the fuel cooler core is designed for the incoming fuel to flow and circulate across the exterior of the heat exchanger prior to exiting. The second primary component includes a filter head assembly with various inlets, outlets, and passageways. The filter head assembly is attached directly to the fuel cooler core so as to deliver coolant into the heat exchanger.

Abstract: A unitized fuel supply assembly is disclosed including an in-line reciprocating cam driven pump (14) for supplying fuel to an accumulator (12) from which fuel is directed to a plurality of engine cylinders by means of a distributor (16) mounted on the unitized assembly. Dual pump control valves (20) provide fail safe electronic control over the effective pump displacement. One or more injection control valves mounted on the distributor are provided to control injection timing and quantity. The accumulator (12) contains a labyrinth of interconnected chambers (36) which are shaped and positioned to produce a minimum overall package size while providing for easy manufacture.

Abstract: A system and method for detecting and correcting power imbalance between cylinder banks of an internal combustion engine utilizes, in one embodiment, temperature sensors at the exhaust manifolds for each cylinder bank. A differential temperature value .DELTA. is generated and used to determine which cylinder requires modification of its operating conditions to equalize the power output between the opposing banks. In one embodiment, the sign of the value .DELTA. is used to determine which cylinder bank has the highest exhaust temperature, and the value .DELTA. is provided as a multiplier to engine operating algorithms implemented by the engine control computer to derate the subject cylinder bank. In another embodiment, the value .DELTA. is used to uprate the bank having the lower exhaust temperature, indicative of a lower power output.

Abstract: A fuel injector for effectively preventing excessive loading of a component mounted internal to the injector is provided which includes a one-piece retainer having first and second connector portions for permitting two independent loads to be applied to different internal components of the injector. The second connector portion includes threads for engaging a nozzle assembly to impart a compressive force on the nozzle assembly. The first connector portion also includes threads for engaging an outer barrel for placing a first compressive load on a load sensitive internal component, such as a center tube of an injection control valve. In this manner, the second compressive force can be set at a minimum level independent from the first compressive force to permit the size of the center tube to be minimized thereby reducing the overall size of the injector.

Abstract: An engine system with a gear train to provide engine timing is disclosed. A technique to minimize backlash and noise caused by the gear train is included. An anti-backlash gear assembly useful to reduce backlash in the gear train is also disclosed. One disclosed gear assembly has at least two gear wheels with the circular thickness of the teeth of one gear wheel being less than the circular thickness of the other gear wheel. A gear assembly is also disclosed that has a bias torque of at least about 100 foot-pounds. A device carried on an anti-lash gear assembly to generally align teeth of the assembly for installation is also provided.

Abstract: A system and method for detecting a misfire condition for a cylinder of an internal combustion engine is based upon the firing times for each cylinder and a comparison of firing times between successive cylinders in the engine firing sequence. A differential firing time parameter represents the result of this comparison and is used a passive test to determine whether a particular cylinder is misfiring. Cylinders identified in the passive test are subjected to an active test in which the cylinder is overfueled by increasing amounts for each engine cycle after commencement of the active misfire test. The change in differential firing parameter for the identified resulting from the overfueling is compared to an active test threshold value indicative of an expected change for a healthy cylinder. A cylinder falling outside this active threshold value is determined to be a bad cylinder.

Abstract: A replaceable cylinder liner for an internal combustion engine having a liner stop positioned within a cylinder cavity at a point intermediate the extremes of travel of a piston disposed for reciprocating travel within the cylinder cavity. The liner includes a hollow cylinder body having an inner end portion and an outer end portion. The liner further includes a liner support for axially supporting the hollow cylindrical body within the cylinder cavity with the liner support including a liner stop engaging surface for engaging the liner stop when the liner is placed within the cylinder cavity. Formed in an outside surface of the outer end portion between the end boss and liner support is an annular recess extending over substantially an entire length of the outer end portion to form a liner coolant passage when the liner is positioned in the cylinder cavity.

Abstract: An engine includes a gear train to provide engine timing. There is a technique for minimizing the backlash and noise caused by the gear train. There is also an anti-backlash gear assembly useful to reduce backlash in the gear train. One gear assembly has at least two gear wheels with the circular thickness of the teeth of one gear wheel being less than the circular thickness of the other gear wheel. There is also a gear assembly having a bias torque of at least about 100 foot-pounds. There is also a device carried on an anti-lash gear assembly to generally align teeth of the assembly for installation.

Abstract: The present invention provides an internal combustion engine drive train actuating assembly which includes a dual overhead cam shaft arrangement wherein a pair of cam shafts is supported in the head section of the engine. One cam shaft is positioned to actuate the intake and exhaust valves. The other cam shaft is dedicated to actuating only the unit fuel injectors and is positioned relative to the injector actuating rocker levers to contact only these rocker levers during engine operation. The rocker lever-contacting lobes on the dedicated injector-actuating cam shaft are dimensionally wider than has heretofore been possible, which allows the high fuel injection pressures required to achieve optimum fuel economy and emissions while minimizing hertz stresses on the cam shaft.

Abstract: An improved method and system for automatically continuously replacing an engine's used lubricating oil with fresh lubricating oil throughout operation based on engine operating conditions is disclosed. The present system includes an lube oil replacement pump system operable in a replacement mode for injecting small amounts of used lube oil into the engine's fuel system and directing controlled quantities of fresh oil into the engine's lube oil system to replace the removed oil. The process periodically determines an engine operating severity value, i.e. fuel consumption value, for an interval of engine operation and calculates a base line quantity of oil for injection based on the current fuel consumption of the engine during the current interval. The lube oil replacement pump may also be operated in a makeup mode for adding quantities of fresh oil to the engine lube oil sump to compensate for oil consumed by the engine.

Abstract: A method and apparatus for controlling engine speed during power take-off (PTO) operation. A technique is disclosed which enables accelerator pedal over-ride of PTO operation, wherein PTO operation is resumed when the accelerator pedal induced engine speed value decreases to a preset PTO engine speed. Also, a high-speed governor is employed to limit accelerator pedal-based engine speed during PTO over-ride operation to thereby limit maximum engine speed. In accordance with the invention, the operator of a vehicle can thus accelerate the engine, via actuation of the accelerator pedal, to engine speeds in excess of the preset PTO engine speed without disengaging PTO operation.

Abstract: A system and method for engine parameter trending in which the engine control module (ECM) periodically stores to non-volatile memory various engine operating parameters over the life of the engine. The system is configurable such that a variable number of samples of a variable number of engine parameters can be stored. In addition to storing each engine parameter, each write to non-volatile memory is also time stamped. This data is used to track the health of the engine over its life cycle. Such data can be useful in providing decreased down time due to increased troubleshooting ability. The system includes a variable number of calibratable predetermined trigger points available so that the data is always logged under the same operating conditions. All triggers must be satisfied for a specified time in order to ensure consistent engine operating conditions when each data set is taken.