Development of an Injector Fault Insertion Tool for DI Gasoline and Diesel Engines

In order to ensure that every portion of the emission control software in a vehicle works, all fault conditions must be tested. Simply simulating faults in the software of the engine controller and reporting it to the OBD II scanner is inadequate; the fault condition must be injected externally to the Engine Control Unit (ECU). In the case of hard-to-reproduce mechanical failures, this is a challenging task. This paper discusses the development of a system capable of emulating various faults that a fuel injector can have while operating as part of a complete working vehicle. For the ECU to operate properly, all fuel injectors must be present in the vehicle, be fully functional, and must represent an accurate electrical load to the ECU. Then, the induced faults must be seamlessly inserted into the running system in less than 10μs and removed before the subsequent injection event. This was accomplished with a variety of COTS hardware, a simple custom circuit, and the use of a large, flexible FPGA platform.