Is this a good waveform for a mag crank position sensor?
 

I tested a suspected bad mag sensor (crank position sensor) with an oscilloscope. I tested it while cranking with the sparkplugs out - first at the sensor plug, and then at the Motec ECU plug to hopefully account for possible bad wiring.

Do these waveforms look OK? Two observations:
- The center line looks a little fatter than I expected.
- One of the waveforms in the first screen shot looks mis-shaped. Could this represent some interference that could cause issues in the signaling to the ECU? I'm not sure if this is within the realm of normal to see in the output of an oscilloscope.

Thanks!

http://forums.pelicanparts.com/uploa...1636342975.jpg

http://forums.pelicanparts.com/uploa...1636342989.jpg

Voltage is vertical axis
frequency is horizontal axis

slight voltage variations on both positive and negative pulses on 2nd screen is my see
frequency periods all seem the same too

voltage levels will vary with RPM. Normal.

The only part of interest to the receiving electronics (ie. the Motec) is the negative going transition through 0v. So the noise on the 4th pulse on the first trace would potential cause multiple triggers because of multiple zero crossings in the noise. That is of course, if it is really noise and not just a bad measurement.