The burrs and clutter on the waveform in a poor ignition state are caused by individual combustion times or series of combustion events that are incomplete or do not burn at all. It leads to the utilization of the effective oxidation part in the cylinder, and the remaining excess oxygen flows into the exhaust pipe and passes through the oxygen sensor. When the sensor detects a change in the oxygen composition in the exhaust, it quickly generates a low pressure or burr, and a series of these high-frequency burrs form what is called a "clutter".