An IBM PS/2 based general purpose engine analyzer

Novel concepts in the design of hardware and algorithms for the diagnosis of a broad range of engine malfunctions and an architecture for general purpose engine analyzers which is based on a clock and sampling signal based on engine angular position are described. The system is based on an IBM PS/2 model 70 portable, chosen for its power, portability, and compatibility with existing PC systems. The system features a number of original algorithms. The scheme consists of an analog preprocessing system which considerably lightens the computational burden of the CPU, and of a set of fast algorithms for the estimation of individual cylinder-produced torque and the instantaneous detection of misfiring cylinders. Among the functions performed by the analyzer are idle speed stability and cylinder power balance, misfire detection, compression checks, fuel injector diagnostics, 0₂ sensor and catalyst diagnostics. In addition, the data acquisition hardware is compatible with the implementation of model-based detection filters, useful for the diagnosis of sensor and actuator failures