A system according to the principles of the present disclosure includes a boost control module and a temperature estimation module. The boost control module generates a wastegate command signal to control a position of a wastegate and thereby adjust an amount of exhaust gas allowed to bypass a turbine of a turbocharger through the wastegate. The temperature estimation module estimates at least one of a first temperature downstream from the turbine and a second temperature upstream from the turbine based on the wastegate command signal.