adding an amp + sub to factory system

[jester]

I haven't removed the deck to check it, is there room for addition back there?

sorry, a bit of car audio ignorance over here..

[MeGaXmAn27]

yes

[bme107]

You can add an amp to the factory system by splicing into the speaker wires at any point in the system. If you meant, are there preamp outputs in the back of the stock head unit, then the answer is no.