Methods and systems are provided for mitigating engine pre-ignition based on a feed-forward likelihood of pre-ignition and feedback from a pre-ignition event. In response to an indication of pre-ignition, a cylinder may be enriched while an engine load is limited. The enrichment may be followed by an enleanment to restore exhaust catalyst feed-gas oxygen levels. The mitigating steps may be adjusted based on engine operating conditions, a pre-ignition count, as well as the nature of the pre-ignition.

Method and system for pre-ignition control

Method and systems are provided for controlling a vehicle system including an engine that is selectively deactivated during engine idle-stop conditions. One example method comprises, adjusting a brake torque applied to a deactivated rotating engine after an engine restart request, the brake torque applied to slow the engine to at least a predetermined threshold speed without stopping the engine, and engaging a starter to the still rotating engine to increase the engine speed and restart the engine.

Methods and systems for assisted direct start control

An engine starting system includes a throttle valve, an alternator, an engine speed sensor and an electronic control unit (ECU). The ECU functionally includes an automatic engine stop controller for automatically stopping the engine by interrupting fuel injection when predefined automatic engine stop conditions are satisfied, and an automatic engine restart controller for automatically restarting the engine when predefined engine restart conditions are satisfied. The automatic engine stop controller sets the quantity of intake air at a level higher than a minimum quantity of intake air necessary for keeping the engine running, decreases the amount of electric power generated by the alternator in an early part of automatic engine stop control operation, and decreases the quantity of intake air and causes the alternator to once decrease the amount of electric power generated thereby at a point in time when the engine speed drops down to a predetermined reference engine speed, and causes the alternator to later increase the amount of electric power generated thereby.

Engine starting system

A device for detecting the deterioration of a catalytic converter for an engine having two or more cylinder groups, and a catalytic converter disposed in a common exhaust passage with which exhaust passages individually connected to the respective cylinder groups are merged, wherein the air-fuel ratio of the respective cylinder groups are controlled independently based on the output of the upstream air-fuel ratio sensors disposed in the respective individual exhaust passages. Since the air-fuel ratios of the respective cylinder groups are controlled independently, the phases of the air-fuel ratio oscillations of exhaust gases flowing into the common exhaust passage from the individual exhaust passages are usually not synchronized. However, during the engine operation, the phases of the air-fuel ratio oscillations of the exhaust gases are occasionally spontaneously synchronized due to slight differences of the periods of the cycle of the air-fuel ratio feedback controls in the respective cylinder groups. The device detects such a spontaneous synchronization, and determines whether or not the catalytic converter has deteriorated based on the output of the downstream air-fuel ratio sensor disposed in the common exhaust passage downstream of the catalytic converter.

A device for determining deterioration of a catalytic converter for an engine

An exhaust emission control device for an internal combustion engine, capable of supplying a just enough amount of reducing agent to a selective reduction catalyst even when a NOx purification ratio of the catalyst is changed by various causes, thereby enabling a high NOx purification ratio and very low exhaust emissions to be maintained. An ECU calculates a filtered value based on a signal from an exhaust gas concentration sensor, calculates a moving average value of a product of the filtered value and a reference input, calculates a control input such that the moving average value becomes equal to 0, and adds a reference input to the control input to calculate an FB injection amount. The ECU calculates an FF injection amount with a predetermined feedforward control algorithm, and adds the FF injection amount to the FB injection amount, to thereby calculate a urea injection amount.

Exhaust emission control device for internal combustion engine

An engine starting system for a power train including an engine and an automatic transmission includes an engine stop/restart controller. The automatic transmission having special mode includes first and second planetary gear sets having respective sun gears, a turbine shaft, an output gear, a forward clutch and a 2-4 brake. The forward clutch sets the automatic transmission in a drive condition when engaged and in a neutral condition when disengaged. If the special mode is selected under conditions where the output gear is locked, the sun gear of the first planetary gear set is locked. During execution of automatic engine stop control operation, the engine stop/restart controller causes the automatic transmission to initiate a transfer to the special mode before fuel supply is interrupted and causes the forward clutch to completely engage at a specific point in time after the automatic transmission has completed the transfer to the special mode.

Engine starting system for power train

A fuel injection control system for a direct injection-spark ignition engine determines an injection pulse width corresponding to a given quantity of fuel with which an injector is kept open, controls the injector to spray a given quantity of fuel in a compression stroke while the engine operates in a zone of lower engine loads specified for lean stratified charge combustion so that the fuel is stratified around an ignition plug to cause lean stratified charge combustion so as thereby to provide an air-fuel ratio greater than a stoichiometric air-fuel ratio, executes fuel injection feedback control to control a quantity of fuel injection based on an air-fuel ratio detected by an oxygen sensor, causes the injector to spray a given quantity of fuel through a plurality of intake stroke split injection in a specified engine operating zone in which the fuel injection feedback control is performed to maintain at least a stoichiometric air-fuel ratio while the engine operates with lower loads, learns a fuel injection quantity characteristic of the injector with respect to injection pulse width for each intake stroke split injection based on a value controlled by the fuel injection feedback control during execution of the intake stroke split injection to determine a leaning correction value, and makes the learning correction value reflect on the control of the quantity of fuel in a minute injection zone specified within the specified engine operating zone for the lean stratified charge combustion.

Fuel injection control system for direct injection-spark ignition engine

An engine control system for a direct injection-spark ignition type of engine determines a target load based on an engine speed and an accelerator pedal travel, determines target air-to-fuel ratio based on an amount of intake air and the target engine load, and determines an amount of fuel injection based on the target air-to-fuel ratio, so as thereby to control engine output torque balancing the target engine load even during a transitional operating state.

Control system for an engine

PROBLEM TO BE SOLVED: To secure ignition stability of mixture gas by maintaining a balance condition of spray penetration of fuel and strength of a tumble flow T without excessively lowering fuel pressure even on a high load side (S1), where an injection volume of the fuel tends to get large and the spray penetration of the fuel gets easily large in a stratified charge combustion area, in a spark ignition type direct jet engine 1, wherein an injector 18 is installed on the peripheral edge of a combustion chamber 6, and the fuel is injected opposing to the tumble flow T of the combustion chamber 6 in a compression stroke of a cylinder 2, so that mixture gas is stratified around an electrode of an ignition plug 16. SOLUTION: The fuel is divided into two and injected by the injector 18 on the high load side (S1) in a stratified charge combustion area during a period after the middle portion of the compression stroke of the cylinder 2. Thereby, the spray penetration of the fuel is lowered, so as to be approximately balanced with the strength of the tumble flow T. On a low load side (S2) of the stratified charge combustion area, the fuel is injected at once by the injector 18 during a period after the middle portion of the compression stroke of the cylinder 2. The exhaust gas is circulated through an EGR passage 33 in the entire stratified charge combustion areas (S1, S2). COPYRIGHT: (C)2003,JPO

Control system for spark ignition type direct injection engine

A fuel injection control system for a direct injection-spark ignition type of engine (1) forcibly turns off
appliances as an external engine load while the engine (1) operates in a stratified charge combustion mode after
warming-up so as thereby to fix a quantity of intake air approximately constant and concurrently feedback
controls a quantity of fuel injection according to an engine speed so as to bring the engine speed into a specified
idling speed An actual quantitative variation of fuel injection is learned on the basis of a feedback correction
value of the quantity of fuel injection for each of predetermined fuel injection timings which are changed from
a timing for minimum advance for best torque (MBT) so as to correspond to injection pulse widths within a
region adopted for a micro-flow characteristic of the fuel injector (12).

Kiyotaka Mamiya

Papers

Engine starting system for power train

Fuel injection control system for direct injection-spark ignition engine

Control system for an engine

Control system for spark ignition type direct injection engine

Method and system for controlling fuel injection for direct inject-spark ignition engine