Crankshaft sensor waveform

What could be wrong with this waveform

It seems to not be the same pattern koec but when it's running it's equal pattern.

Why does your trace keep slowing down? What scope are you using?
What I saw looks like a scope issue. Not enough sampling, too long of a time base, incorrect or poor contact with the sensor...

This is a played back capture not live. I was scrolling through the frames. It's the modis.
I was wondering why is the some of the waves look distorted. It only looks like that on a koec test but if it fires up its clean looking waveform.

The harmonic pulley has 4 notches that go over the cps. This is a 2 wire cps . However during cranking it appears to only show one clean waveform than the second one is somewhat looks distorted then the third waveform is clean and pattern repeats with different levels of distort third waveform.

If the car starts up its all clean waveforms

Is it possible the cps is faulty while cranking ?