Free Mint 14 has a version of Mplayer with a built in  oscilloscope.
All you guys struggling with your EFI can use this to check CAS's
and other EFI pulse situations. Just connect the probe to the mic
input. Use a pot and 5 volt zener to limit the input voltage.

It is worth downloading free Mint and burning live DVD just
so you have access to this program.

Paul Lamar