Control system for compression ignition internal combustion engine

A control system for a compression ignition internal combustion engine that has a fuel injection valve, which injects fuel into a corresponding cylinder of the engine, the control system comprising:

• a control means for determining target ignition timing based on operational information of the engine and for adjusting a fuel injection mode at the fuel injection valve according to the target ignition timing;
• an oxygen information obtaining means for obtaining oxygen information of exhaust gas, which is exhausted from the cylinder of the engine;
• and
• a correcting means for correcting the target ignition timing based on the oxygen information, which is obtained by the oxygen information obtaining means, with reference to predefined constant torque characteristic data, which indicates a relationship between the oxygen information and ignition timing for achieving a generally equal constant torque.