Abstract: A control system for estimating the performance of a compressor is disclosed. The control system has a compressor fluidly connected to an inlet manifold of a power source. The control system also has a power source speed sensor to provide an indication of a rotational speed of the power source, an inlet pressure sensor to provide an indication of a pressure of a fluid within the inlet manifold, an inlet temperature sensor to provide an indication of a temperature of the fluid within the inlet manifold, an atmospheric pressure sensor to provide an indication of an atmospheric pressure, and a control module in communication with each of the sensors. The control module is configured to monitor an engine valve opening duration and an exhaust gas recirculation valve position, and estimate a compressor inlet pressure based on the provided indications, the monitored duration, and the monitored position.