Patent ID: 7444984

Claim:
A control system for an internal combustion engine having fuel injection means for injecting fuel into a combustion chamber of said engine, said control system comprising: fuel injection control means for controlling said fuel injection means; exhaust gas recirculating means for recirculating a portion of exhaust gases from said engine to said combustion chamber; exhaust cooling means for cooling the exhaust gases that are recirculated, wherein said exhaust cooling means is included in said exhaust gas recirculating means; target ignition timing calculating means for calculating a target ignition timing of the fuel injected by said fuel injection means; ignition timing detecting means for detecting an actual compression ignition timing of the fuel injected by said fuel injection means; and exhaust cooling control means for controlling an operation of said exhaust cooling means based on the target ignition timing and the actual compression ignition timing; wherein said fuel injection control means has first and second fuel injection timing maps which are set according to an operating condition of said engine, wherein said fuel injection control means uses the first fuel injection timing map when said exhaust cooling means is not operating or when said exhaust cooling means is operating and a delay of the actual compression ignition timing with respect to the target ignition timing is greater than a predetermined threshold value, and wherein said fuel injection control means uses the second fuel injection timing map when said exhaust cooling means is operating and the delay of the actual compression ignition timing with respect to the target ignition timing is equal to or less than the predetermined threshold value.