摘要:
When a wastegate valve, which opens and closes an exhaust bypass passage bypassing an exhaust turbine, is open, exhaust gases of respective cylinders bypass the exhaust turbine and pass a sensing point of an air-fuel ratio sensor downstream of the exhaust turbine. Accordingly, the exhaust gases of the respective cylinders can be avoided from being mixed by the exhaust turbine, so an influence of an inter-cylinder variation in an air-fuel ratio due to an inter-cylinder imbalance abnormality becomes apt to appear in an output waveform of the air-fuel ratio sensor. Therefore, existence or nonexistence of the inter-cylinder imbalance abnormality is determined based on the output of the air-fuel ratio sensor when the wastegate valve is open. Eventually, the existence or nonexistence of the inter-cylinder imbalance abnormality can be determined accurately, thereby improving detection accuracy of the inter-cylinder imbalance abnormality.
摘要:
A fuel injector for an internal combustion engine which has a spray hole designed geometrically to produce a spray of fuel so that substantially 70% or more of an amount of the spray hits a preselected area of a head of an intake valve of the engine when the intake valve is closed. The preselected area is one of a first and a second area of the intake valve head which are defined by a reference boundary line extending through a base end of a stem of the intake valve. The preselected area is the first area closer to an intake manifold, while the second area is closer to an exhaust valve. This avoids rich misfire and reduces HC emissions from the engine regardless of the intake valve is in a closed state or in an open state.
摘要:
A bypass passage for bypassing a check valve is connected with a vacuum introducing passage of a brake booster. The bypass passage is provided with a switching valve. Just before the start of an engine, the switching valve temporarily opens the bypass passage whereby to equalize a remaining pressure of the brake booster substantially becomes equal to an atmospheric level. As a result, the pressure in the brake booster at the starting time is set to substantially the atmospheric level so that the airflow to be sucked from the brake booster into the intake pipe at the starting time is made substantially contact every times. Thus, the fuel injection rate can be set considering the airflow to be sucked from the brake booster into the intake pipe at the starting time, even if that airflow cannot be detected.
摘要:
A fuel injector for an internal combustion engine which has a spray hole designed geometrically to produce a spray of fuel so that substantially 70% or more of an amount of the spray hits a preselected area of a head of an intake valve of the engine when the intake valve is closed. The preselected area is one of a first and a second area of the intake valve head which are defined by a reference boundary line extending through a base end of a stem of the intake valve. The preselected area is the first area closer to an intake manifold, while the second area is closer to an exhaust valve. This avoids rich misfire and reduces HC emissions from the engine regardless of the intake valve is in a closed state or in an open state.
摘要:
The present invention has an object to provide an exhaust gas purifying apparatus for an internal combustion engine capable of obtaining accurate temperature information relating to a catalyst placed in an exhaust passage of the internal combustion engine. The degree of influence emthc of a catalyst inlet gas temperature and catalyst rear end temperature ethuf[end] is calculated (Step 102). An estimated value ethco of an outlet gas temperature is calculated by weighted averaging the inlet gas temperature and the catalyst rear end temperature ethuf[end] considering the degree of influence emthc (Step 104). A temperature correction coefficient ekthuf[x] for each region of the catalyst is calculated as a function f(emthc) of the degree of influence emthc (Step 108). A deviation between the outlet gas temperature estimated value ethco and a measured value of the outlet gas temperature is multiplied by the temperature correction coefficient ekthuf[x] to calculate an estimated value correction amount ecthuf[x] (Step 110). The estimated value correction amount ecthuf[x] is added to a catalyst temperature estimated value (Step 114).
摘要:
The present invention has an object to provide an exhaust gas purifying apparatus for an internal combustion engine capable of obtaining accurate temperature information relating to a catalyst placed in an exhaust passage of the internal combustion engine. The degree of influence emthc of a catalyst inlet gas temperature and catalyst rear end temperature ethuf[end] is calculated (Step 102). An estimated value ethco of an outlet gas temperature is calculated by weighted averaging the inlet gas temperature and the catalyst rear end temperature ethuf[end] considering the degree of influence emthc (Step 104). A temperature correction coefficient ekthuf[x] for each region of the catalyst is calculated as a function f(emthc) of the degree of influence emthc (Step 108). A deviation between the outlet gas temperature estimated value ethco and a measured value of the outlet gas temperature is multiplied by the temperature correction coefficient ekthuf[x] to calculate an estimated value correction amount ecthuf[x] (Step 110). The estimated value correction amount ecthuf[x] is added to a catalyst temperature estimated value (Step 114).