Patent ID: 8490598

Claim:
A method for controlling an internal combustion engine having an ignition coil associated with at least one spark plug, the method comprising: generating a pre-discharge ionization signal during charging of the ignition coil after reaching a first threshold charge level and prior to spark discharge; determining engine operating condition in response to the pre-discharge ionization signal; generating a first digital feedback signal in response to a coil charging signal until the ignition coil reaches the first threshold charge level, the first threshold charge level being less than a spark discharge charge level; generating a second digital feedback signal in response to the ignition coil being above the spark discharge charge level and no charging signal being present; controlling number and duration of repetitive spark discharges during a single combustion cycle in a single cylinder in response to at least the first and second digital feedback signals; transmitting the first and second digital feedback signals by a common wire; and determining operating condition of the at least one spark plug associated with the second ignition coil in response to the pre-discharge ionization signal on the common wire, wherein generating a pre-discharge ionization signal includes generating a third digital signal in the first ignition coil to mask the pre-discharge ionization signal.