Why Doesn't it Charge Properly?

Hello all. I have a Macbook MacBook Pro 15" Core 2 Duo Models A1226 and A1260. I have had trouble charging it. Sometime when I plugged in the charger it would charge and another times it would not. I replaced the charger with a known good one. I am still having the same problem. The connector shows green, stating it is charged, but it is not. If i slightly wiggle the conenctor, where it plugs into the laptop, it will eventually go orange and begin charging. What can I do?