A control system of an engine is provided. The control system includes an inlet sensor configured to generate a signal indicative of an engine inlet air temperature and an intake manifold sensor configured to generate a signal indicative of an engine intake manifold air temperature. The control system includes a control module communicably coupled to the inlet sensor and the intake manifold sensor. The control module is configured to determine the engine inlet air temperature and the engine intake manifold air temperature. The control module is configured to determine an initial de-rate value based on a predetermined relationship between the engine inlet air temperature and the engine intake manifold air temperature. The control module is configured to determine a pre-stored de-rate modifier corresponding to an engine speed. The control module is configured to determine a final de-rate value based on the initial de-rate value and the pre-stored de-rate modifier.