A system includes a reciprocating internal combustion engine with one or more reaction zones configured to receive a charge flow that is configured to react within the one or more reaction zones, thereby forming an exhaust gas flow, and a controller. The charge flow includes an oxidant flow, a fuel flow, and a recirculated portion of the exhaust gas flow. The controller is configured to control a ratio of the recirculated portion of the exhaust gas flow to a fuel mixture. The controller controls the ratio based at least in part on a first temperature, a second temperature of the charge flow, and a third temperature of the recirculated portion of the exhaust gas flow. The fuel mixture includes the oxidant flow and the fuel flow. The first temperature includes one or any combination of a sensed temperature of the oxidant flow, the fuel flow, or the fuel mixture.