A method of identifying air flow faults within a cooling system of an automobile comprises measuring the temperature of coolant entering a heat exchanger for the cooling system, measuring the temperature of coolant leaving the heat exchanger, and measuring the temperature of ambient air that is flowing into the heat exchanger, calculating Actual Delta T by subtracting the temperature of coolant leaving the heat exchanger from the temperature of coolant entering the heat exchanger, calculating Expected Delta T, wherein Expected Delta T is a pre-determined value of an expected difference between the temperature of the coolant entering the heat exchanger and the temperature of the coolant leaving the heat exchanger, calculating Effective Delta T by subtracting Expected Delta T from Actual Delta T, and identifying a fault in the air flow through the heat exchanger based on the value of Effective Delta T.