摘要:
An abnormality detection apparatus for a multi-cylinder internal combustion engine changes a fuel injection quantity of a predetermined target cylinder to detect an abnormality of an internal combustion engine based on values of rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity. The abnormality detection apparatus corrects the values of the rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity based on at least one of the number of revolutions of the engine and an engine load at a corresponding detection time.
摘要:
An apparatus for detecting imbalance abnormality in an air-fuel ratio between cylinders in a multi-cylinder internal combustion engine according to the present invention increases a fuel injection quantity to a predetermined target cylinder to detect imbalance abnormality in an air-fuel ratio between cylinders at least based upon a rotation variation of the target cylinder after increasing the fuel injection quantity. The increase in the fuel injection quantity is carried out in the middle of performing the post-fuel-cut rich control. Since timing of the post-fuel cut rich control is used to increase the fuel injection quantity, the exhaust emission deterioration due to abnormality detection execution can be prevented as much as possible.
摘要:
An abnormality detection apparatus for a multi-cylinder internal combustion engine changes a fuel injection quantity of a predetermined target cylinder to detect an abnormality of an internal combustion engine based on values of rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity. The abnormality detection apparatus corrects the values of the rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity based on at least one of the number of revolutions of the engine and an engine load at a corresponding detection time.
摘要:
An apparatus for detecting imbalance abnormality in an air-fuel ratio between cylinders in a multi-cylinder internal combustion engine according to the present invention increases a fuel injection quantity to a predetermined target cylinder to detect imbalance abnormality in an air-fuel ratio between cylinders at least based upon a rotation variation of the target cylinder after increasing the fuel injection quantity. The increase in the fuel injection quantity is carried out in the middle of performing the post-fuel-cut rich control. Since timing of the post-fuel cut rich control is used to increase the fuel injection quantity, the exhaust emission deterioration due to abnormality detection execution can be prevented as much as possible.
摘要:
An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The apparatus determines imbalance of an air-fuel ratio among the cylinders based on a difference between index values correlated with crank angular velocities detected in a set of opposite cylinders belonging to different banks and having crank angles different from one another by 360°; and carries out an air-fuel ratio feedback process for controlling an amount of injected fuel for each of the banks, wherein the apparatus comprises a correction unit correcting, before determining the air-fuel ratio imbalance, the difference between the index values in a direction of combustion improvement for opposite cylinders that are opposite to cylinders belonging to a bank identical to a bank of a cylinder with the most deviating index value from a standard value among all the cylinders and being other than the cylinder with the most deviating index value.
摘要:
An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The apparatus determines imbalance of an air-fuel ratio among the cylinders based on a difference between index values correlated with crank angular velocities detected in a set of opposite cylinders belonging to different banks and having crank angles different from one another by 360°; and carries out an air-fuel ratio feedback process for controlling an amount of injected fuel for each of the banks, wherein the apparatus comprises a correction unit correcting, before determining the air-fuel ratio imbalance, the difference between the index values in a direction of combustion improvement for opposite cylinders that are opposite to cylinders belonging to a bank identical to a bank of a cylinder with the most deviating index value from a standard value among all the cylinders and being other than the cylinder with the most deviating index value.
摘要:
A fuel injection amount control apparatus includes an air-fuel ratio sensor which is disposed between an exhaust gas merging portion HK and an upstream catalyst. The control apparatus performs a feedback correction on an amount of fuel to be injected by the fuel injection valve in such a manner that an air-fuel ratio represented by an output value of an upstream air-fuel ratio sensor becomes equal to a target air-fuel ratio which is set at stoichiometric air-fuel ratio. The control apparatus obtains an air-fuel ratio imbalance indicating value, which becomes larger as a difference in air-fuel ratio of each of the mixtures supplied to each of the combustion chambers among the cylinders becomes larger, and performs an increasing correction to the amount of fuel to be injected by the injection valve in such a manner that an air-fuel ratio becomes a richer air-fuel ratio than the stoichiometric air-fuel ratio as the obtained air-fuel ratio imbalance indicating value becomes larger.
摘要:
A control device of an internal combustion engine according to the present invention has units configured to inject fuel at a first predetermined ratio from first and second fuel injection valves which are provided in each of cylinders to calculate a first value indicating a degree of variation in air-fuel ratios between the cylinders based on a output of the engine, and inject fuel at a second predetermined ratio therefrom to calculate a second value in the same manner. Furthermore, the control device has a unit configured to select one mode from modes relating to abnormality in the first fuel injection valve or the second fuel injection valve on the basis of the first and second values, and calculate a value indicating the degree of the variation in the air-fuel ratios between the cylinders, thereby calculating a fuel amount of the basis of them.
摘要:
A control device of an internal combustion engine according to the present invention executes air-fuel ratio control based on an output of an air-fuel ratio sensor provided at an upstream side of a catalyst, with correction based on an output of an oxygen sensor at a downstream side of the catalyst. When it is determined that a degree of an output tendency in a predetermined lean region is not less than a predetermined lean degree, and that a degree of an output tendency in a predetermined rich region is less than a predetermined rich degree based on lean tendency and rich tendency values representing output tendencies of the oxygen sensor, a limit is set to the correction in a direction to more suppress enriching of an air-fuel ratio as a degree is larger in which the output of the oxygen sensor is shifted to a lean side.
摘要:
A fuel injection amount control apparatus comprises an air-fuel ratio sensor disposed between an exhaust gas merging portion and an upstream catalyst. The control apparatus performs a feedback correction on an amount of fuel to be injected by the fuel injection valve so that an air-fuel ratio represented by the output value of the upstream air-fuel ratio sensor becomes equal to a target air-fuel ratio set at stoichiometric air-fuel ratio. The control apparatus obtains an air-fuel ratio imbalance indicating value, which becomes larger as a difference in air-fuel ratio of each of the mixtures supplied to each of the combustion chambers among the cylinders becomes larger, and performs an increasing correction to the instructed fuel injection amount in such a manner that an air-fuel ratio determined by the instructed fuel injection amount becomes richer than the stoichiometric air-fuel ratio as the obtained air-fuel ratio imbalance indicating value increases.