You have overkill on your sample rate sampling every 50 billionths of a second. So, you will get every bit of noise. That spike looks like a bit of ignition RFI to me.
With more events on the screen, you would probably see more of them at regular intervals. You can confirm the source by dial tracing the ignition to see if it matches up.
_________________
Tom Roberts
(The Picotologist) http://www.autonerdz.com
skype: autonerdz
THE PicoScope Automotive Authority
In North America
You adjust the requested number of samples in the top control bar to the right of the horizontal zoom control. Then monitor the effect in the properties tab info on the right.
Think of the number of samples control like the gas pedal and the properties tab the speedometer. Many things can affect the actual sample rate result. Capture time, number of channels, slow sampling transition point, hardware, etc. So just keep an eye on the speedometer for the desired effect until you get used to how she handles.
_________________
Tom Roberts
(The Picotologist) http://www.autonerdz.com
skype: autonerdz
THE PicoScope Automotive Authority
In North America