F 150 4WD Pickup V8-302 5.0L (1986)
5.
Zoom in on the recording as much as possible. Look for timing spikes that REPEAT EVERY EIGHTH FIRING OF THE DIGITAL PIP SIGNAL,
Figure 2.
6.
Move the cursor across all spikes to read the timing difference.
NOTE:
THE SPARK ADVANCE WILL SPIKE UPWARD AT LEAST 20 ON SUSPECT VEHICLES.
7.
Print the graph for warranty use.
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Downward spikes would indicate a retarded spark condition and will NOT cause detonation.
