Nikku

I have a 93' s13 (hatch it if matters) and I have a question about the speakers.
Okay get this, yes I googled it, I still have no clue.

Starting,
I got the car with a crappy old pioneer headunit in it (single din) and when I had it in there only the front speakers worked.

I read online that if you ran new speaker wire (bipassing the factory amp) it would work.

So I did this while I put new carpet in my car, and bought this new headunit to put in it ( Amazon.com: 2013 MODEL PIONEER AVH-X1500 DVD / AVHX1500 DVD In-Dash 6.1 Touchscreen: Car Electronics )

Then when I plugged it all in and turned it on only the rear speakers work?

I have no idea why this could be happening, any suggestions?