US Patent 7860638 Method for determining fuel injection pressure

A method for determining fuel injection pressure or detecting a discrepancy in the fuel injection process of an internal combustion engine is provided. The engine includes a camshaft that actuates at least one fuel injector of the engine's fuel injection equipment. The method includes the step of determining a value T that is representative of the torque generated on the camshaft, such as the instantaneous torque or rotational speed of the camshaft, the torque being a resultant of accelerating and decelerating forces exerted on the camshaft by the at least one fuel injector during a phase of operation of the internal combustion engine. The method also includes the step of monitoring the value T for any increment, decrement or irregularity.