An engine control system for an engine of a vehicle provided with a power steering system having a power steering pump has an engine torque controller for varying output torque of the engine according to engine operating conditions. The engine torque controller is forced to increasingly vary the engine torque when a hydraulic pressure sensor, located just behind, or after, the power steering pump, detects a hydraulic pressure higher than a predetermined hydraulic pressure. The varying action of the engine torque controller is suspended while a temperature sensor, located just before or after the hydraulic pressure sensor, detects a temperature lower than a predetermined temperature.