like i said earlier, the amps in the 460, all three of them: the one in front for the tweeters and the two in back for all 4 6x8s, are line level input amps. by sending a speaker level output to them, (which nearly every headunit does, so that you can run a speaker without an amp) destroys the amps after a while of time. so im guessing that your rear speakers were running off of the stock amps wired wrongly.
the solution? run your own wires from the head unit to your rear speakers. just like lilroush said.

 

ok well there could be a few things 1 i wasnt clear as to whether or not they bypassed the rears ? 2 check back speaker wires and wires behind the deck/radio than if they are all plugged in get a voltage meter touch it to the connectors that go to the speaker terminal see if you have power than we can figure out where to go from there

 

I'm going to try your suggestion LilRoush this Saturday. I now believe, like a lot of you, that my rear speakers were never connected after the head unit was replaced.

 

Okay, so all 3 original amps were not connected to anything. The front speakers and tweeters were connected together to the head unit. The fix for the back speakers was to wire them directly to the head unit, although, when that was done the entire system shut down. The back tweeeters were then disconnected and, waa laa, everything worked! So what I have now is, no Mach 460 amps, front door speakers, front Mach 460tweeters, and back speakers only. I would still like more bass though.

 

rip the whole thing out and start over fresh

mine will be:
Pioneer 5.8” navigations f700bt
MB Quart Dkh 168 6x8 speakers120 (front)
MB Quart DKH 113 5.25” (rear, i have a vert, coupes are 6x8 rear to)
Infinity 1011T tweeters
Profile AP600 amp (2)
JL audio W1 V2 10’ sub 300 rms
Profile AP2000 amp
Steeda Battery relocation
Steeda Battery Box
alternator 200a w/ 4 guage wire

 

wait a minute mustagmann. I have like legit the same car as you and the guy at bestbuy told me I have 6x8's all around. So i put alpine 6x8's in the front and rear. Is it bad or should I do something about it?

 

verts have a 5.25 rears,

http://www.flemworld.com/Mach460/Mach.html

 

Greattt.....well he's an idiot and now I somehow have 6x8's crammed in there. Should I buy a pair of 5.25's and are there any you would reccomend

 

they probably put 5.25" in there to fit and not 6x8, you cant fit something over 6" into a small(er) hole

 

haha yes I understand that. But I bought them from a buddy at bestbuy who gave me a discount so it wasn't "technically" through the store. So they wouldn't replace them on their own. I can check but I'm almost positive they jammed them in there or something.