Originally Posted by BigMuthatrknG
I'm pretty sure it would register a misfire wouldn't it.
Not always. A flashing CEL indicates a misfire on every rpm, but if it's a random misfire, then the computer doesn't always record that. To the ECU, it might not be a misfire because spark signal was sent, but it might not be strong enough to fire the charge.
No, the PCV vacuum line won't be collapsed when the engine is not running. It is engine vacuum that collapses the line.
A loose battery terminal will cause the conditions you've described, and that's where you should start. Remove the terminals, clean, replace. If you find corrosion: I recommend greasing the battery terminal after installing/tightening. That will prevent future corrosion.