Fuel injection control apparatus and fuel injection method

In a fuel injection control apparatus having an operation condition detection means for detecting an engine operation condition, a fuel injection amount establishment means for establishing a fuel injection amount to an engine according to said detected engine operation-condition, and an air-fuel ratio feedback correction means for correcting said fuel injection pulse width according to an air-fuel ratio feedback correction,

• the fuel injection control apparatus further includes wherein,
• a pulse width limitation establishment means for establishing a pulse width limitation value, and
• a control means for carrying out a control which limits a pulse width correction alternation command according to said air-fuel ratio feedback correction means, under a condition in which said pulse width limitation is carried out.

In a fuel injection control apparatus having an operation condition detection means for detecting an engine operation condition, a fuel injection amount establishment means for establishing a fuel injection amount to an engine according to said detected engine operation condition, an air-fuel ratio feedback correction means for correcting said fuel injection pulse width according to an air-fuel feedback ratio correction, and an A/F (air-fuel) learning correction means for A/F learning correcting said fuel injection width according to the A/F learning,

• the fuel injection control apparatus further includes
• a pulse width lower limitation establishment means for establishing a pulse width lower limitation value, and
• a correction width limitation means for limiting the correction, when a calculated fuel injection pulse width according to said air-fuel ratio feedback correction and said A/F learning correction exceeds said pulse width lower limitation value.

In a fuel injection control apparatus having an operation condition detection means for detecting an engine operation condition, a fuel injection amount establishment means for establishing a fuel injection amount to an engine according to said detected engine operation condition, an injection pulse width establishment means for establishing a fuel injection width according to said established fuel injection amount, and an A/F (an air-fuel ratio) learning correction means for A/F learning correcting said fuel injection pulse width according to an A/F learning,

• the fuel injection control apparatus further includes wherein,
• a pulse width limitation establishment means for establishing a pulse width limitation value, and
• means for limiting a renewal of the A/F learning, when said fuel injection width affected and calculated according to said correction of said A/F learning correction means exceeds said pulse width lower limitation value.

In a fuel injection method, comprising

• the steps of detecting an engine operation condition, establishing a fuel injection amount to said engine according to said detected operation condition, establishing a fuel injection pulse width according to said established fuel injection amount, carrying out a fuel injection control according to said established fuel injection pulse,
• effecting a first operation mode for limiting said fuel injection pulse width, and
• effecting a second operation mode for reopening an air-fuel ratio feedback correction and an A/F learning correction, by using an air-fuel ratio feedback correction coefficient or an A/F learning correction coefficient which are limited at said first operation mode.