Late 2008 15" MBP. Turns off when moved

[-tWv-]

Hey everyone, wondered if anyone had any ideas on what the issue is with my computer.

The problem is whenever I bump or tip my MacBook it immediately turns off. When it's stationary it works perfectly, but for some reason loses power when it's tilted or moved at all. I have used it for a few weeks hooked up to a monitor and have a new rMBP on the way, but for the sake of resale value I wanted to see if anyone had an idea on what component could be damaged or loose so I can fix it.

Thanks in advance for any input you may have

 

[LeGacY X]

Possibly a loose internal battery connection. Does the same issue arise when the laptop is pugged in?

 

[-tWv-]

The problem only occurs under battery power.. Must be a loose connection like you said. Is there any way that I could tell by opening it up? I've replaced both the HDD and the RAM as well as done work with iPhones so I'm not completely useless with DIY repairs.