A system includes an air manifold, a fuel manifold, and a plurality of fuel injectors. At least one of the fuel injectors includes a heat exchanger portion for supplying compressed, cooled air form the heat exchanger portion to the air manifold. An air valve is operatively connected to an outlet of the air manifold for controlling release of air from the air manifold. A controller is operatively connected to the air valve, wherein the controller includes machine readable instructions configured to control the air valve to regulate flow of air through the air valve based on fuel temperatures in the fuel channel. The machine readable instructions can be configured to cause the controller to flow air through the air valve in a heat exchange mode if a fuel temperature in the fuel injectors is below a predetermined fuel temperature.