Fiveohwagon

I'm currently working on a 02 tahoe, and the problem is this: The right door tweeter and speaker does not work at all, and the left door speaker and tweater are working, but sound really crappy, the rear speakers work fine.

I found the amp, and someone has spliced into a hand full of wires, some of them being the front door speakers, i assume they installed an aftermarket amp, and took it out when they traded it in. what i'm thinking is this, since they didn't unplug the OE amp, and the aftermarket amp was feeding both the speakers and shoving power into the OE amp, i'm guessing the OE Amp took a crap. all the wires have continuity after i fixed them and i still have the same problem.

Also, when i removed the radio, i found 2 black wires knoted togeather, and 1 was cut, and there is a tan wire that goes no where, and is also cut, all my pins in my radio connectors are full. i'm about to recomend an amp..... any ideas???