Powertrain diagnostics - Part 2 - Detecting injector deactivation failure modes in diesel engines using a crankshaft speed order domain approach

This report documents the investigation of fuel injector fault detection methods for a seven liter diesel engine. This effort was conducted for the Tank Automotive Research Development Engineering Center (TARDEC) Condition Based Maintenance (CBM) team. The task of this investigation was to develop algorithms capable of real-time detection of injector misfire events. The purpose of this task was to enable TARDEC's Engine Control Management (ECM) research and development efforts to evaluate the technical feasibility of integrating automated on-board condition monitoring algorithms with future ECM monitoring and control operations. During this investigation, it has been shown that multiple techniques can correctly detect and identify injector cylinder misfiring. Each individual technique has its own advantages, and this investigation focused on signal processing methods that would be suitable for embedding in an engine controller or processor. The list below includes six injector fault analysis approaches that were evaluated for this effort : 1. Injector signal analysis. 2. Cylinder head vibration analysis. 3. Crankshaft speed analysis in time domain. 4. Crankshaft speed analysis in order domain. 5. FFT classifier selection technique. 6. Time domain classification technique. This paper only highlights the crankshaft speed order domain technique.