90 lumina euro stereo amplified question

Is there a stock amp on this model? I hooked up an aftermarket stereo a very long time ago and have gotten nothing but crap from the rear speakers since. I just installed new speakers thinking the deck was over powering them and still crap for sound. I read that my deck was known for blowing stock amps so I guess my questions are is there one in my car and where? How do I bypass it to hook speakers up. Thanks

There was no factory radio amp available in your year. I would check to be sure you have them wired correctly. If you reverse polarity by accident on one speaker, they will sound like crap.

I've checked the wiring at the stereo harness quite some time ago and it looked ok. Kind of hard to go wrong when it's pretty much color matching. The new rear speakers were hooked up with harnesses as well so I know those are right. I don't know what else it can be if it's still sounds like ass. I will again double check the speaker wires at the head unit in hopes of finding something

insert foot!!! I checked the deck once again and sure enough wires were crossed. For the record I didn't wire up the harness for this install but you'd think I'd have noticed it the first time I checked it. :doh: