Sierra 18-9903 Engine Ignition Analyzer Use the Sierra 18-9903 Engine Ignition Analyzer for diagnosis performance measurement of all types of spark ignition systems. Troubleshoot Non-Starts, Misfires, Intermittent problems, damaged spark plug wires Troubleshoot Fouled or damaged spark plugs, primary secondary coil circuit faults Features Display waveforms in real time Detect display dwell angle and ramp time Graph burn time, spark plug voltage, dwellramp time, RPM for each spark Compare read