Methods and apparatus are disclosed for detecting whether a gear-driven fuel pump has been installed correctly in a fuel injected IC engine, the pump gear being driven by an engine gear to provide fuel to injectors via a fuel rail. The method may include providing a pump element pumping event. The method may also include disabling overlapping fuel injectors and overlapping pumping events during the test period surrounding the selected pumping event, and measuring the pressure in the rail during the pumping event with the overlapping injectors disabled, the at least two different engine crank angles surrounding the pumping event. The method also may further include determining from the measured rail pressures whether the pumping event occurred at a desired engine crank angle. Apparatus to carry out the methods may include a computer programmed for controlling the sequence of the providing, disabling, measuring, and determining functions, as well as software for carrying out the respective functions.