Connect the First Look Sensor to Channel A on the ADC-212 using the 25ft BNC to BNC cable as shown in Figure 1.0, then attach the sensor to a vacuum source on the intake manifold (use the reducer hose if necessary) as shown in Figure 1.1.
Fig. 1.0
Fig. 1.1
Now connect the Secondary Ignition pick-up Lead to Channel B of the scope and attach the clamp to the cylinder 1 plug lead. Once you have disabled the fuel system (may not be possible on a carburated engine), crank the engine until the display pattern stabilizes. You can adjust the timebase and voltage scales to achieve best signal display.
This test is useful in the assessment of the intake air and valve system for cylinder specific defects on the intake side of the engine.
Example FirstLook sensor waveform
FirstLook sensor waveform notes
This waveform shows a consistent signal pattern on Channel A as triggered against Channel B on the same time line. Cursor lines are added to show trigger reference (sparkplug 1) and show the time between trigger events. We can use this information to determine the approximate cranking speed of this engine.
Waveforms will vary from vehicle to vehicle, but should be consistent from cylinder to cylinder. Any variation suggests that one cylinder is drawing in a different amount of air/fuel mixture than the others.
