Abstract: The electronic control module of the new generation of fuel injected internal combustion engines is adapted to compensate for variations in operating temperature or pressure readings among the cylinders, so that cylinders having a low temperature or pressure reading relative to the others will receive an increased flow of injected fuel, whereas cylinders running at a relatively high temperature and pressure compared to the other cylinders will receive a decreased fuel injection, so that the cooler cylinders run hotter and the hotter cylinders run cooler. The uniformity of power delivery among the cylinders, which is the object of the operating temperature and pressure adjustment, yields a more even delivery of power and a more efficient use of fuel.

Abstract: A system for equalizing the performance among the cylinders of an internal combustion engine which involves the introduction of increased fuel to under-performing cylinders, and reduced fuel to over-performing cylinders, with the result that the cylinders all perform at a more uniform level. In the first embodiment, this is achieved by means of selecting unit injectors for a diesel engine according to the cranking compression in each cylinder so that cylinders with lower compression receive more fuel. In the second embodiment, in which injectors in either diesel or gasoline engines are controlled by an electronic controller, temperature sensors within the individual cylinders report to the electrical control unit which then operates the injectors to meter the fuel injection such that hotter operating cylinders receive less fuel and cooler cylinders receive more. The engine is then tuned according to the engine manufacturer's standard procedures.