Tercel Sedan 2-Door L4-1497cc 1.5L DOHC (5E-FE) (1995)
Knock Sensor: Oscilloscope Patterns and Waveforms
INSPECTION USING OSCILLOSCOPE
Knock Sensor Signal Waveform
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Top waveform: With the engine racing (4,000 rpm) measure between terminal KNK of ECM and body ground.
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Bottom waveform: Spread the time on the horizontal axis, and confirm that period of the wave is 123 microseconds
(Normal mode vibration frequency of knock sensor: 8.1 KHz.)
HINT: If normal mode vibration frequency is not 8.1 KHz, the sensor is malfunctioning.