Internal combustion engine

In an internal combustion engine of the type including a combustion chamber having intake and exhaust ports;

• and injection means for injecting a mixture of fuel and oxidizer into said combustion chamber, the improvement comprising:
• means defining an exhaust flowpath for providing communication between said exhaust port and said intake port;
• wherein said injection means comprises means defining a fuel flowpath, including a venturi, for delivering fuel to said combustion chamber and means defining an oxidizer flowpath for delivering oxidizer to said fuel flowpath downstream of said venturi;
• and
• wherein said means defining an exhaust flowpath comprises a branched conduit providing communication between said exhaust port and said intake port, and providing communication between said exhaust port and the ambient atmosphere, a throttle valve disposed in the portion of said branched conduit in communication with said intake port and actuatable for controlling the flow of exhaust gases to said intake port, a sensor disposed in the portion of said branched conduit in communication with said intake port at a position downstream from said throttle valve for developing an output signal representative of the flow rate of exhaust gases at said position, a fuel pump responsive to the sensor output signals for providing fuel under pressure to said means defining a fuel flowpath and for increasing the fuel pressure in response to sensed increases in exhaust gas flow rate, means for applying the sensor output signal to said fuel pump, valve means responsive to the sensor output signal for decreasing the rate of exhaust gas flow into the ambient atmosphere in response to sensed increases in exhaust gas flow rate, and means for applying the sensor output signal to said valve means.