Infinity-right side good,left side bad ???

All speakers on the right, sound good, yet all on the left sound bad - distorted upfront, and the rear you can barely hear at high volume.
Do you think it's the head unit, or the amp, or should I just start tearing things apart and swap, to find out? Also, do you really have to gut the back, in order to replace the rear speakers? I've seen tremendous work posted on other sites, and I can't believe it's that huge of a task!
Thanks for your help!

Sorry for taking so long to get back, but it sounds like you have a defective head unit. Speakers DO go bad but it's ironic that both back speakers would go at the same time. In answer to pulling out speakers, yeah, you gotta pull out the backseat and the C-pillar plastic framing on the inside just to take off the package shelf to get out the speakers on 98-up LH sedans. I did it on my 02 Intrepid, took me half an hour, just taking it out. Good luck.

I actually think its my amp. I have a similar problem with my 98ES. I have really bad output on the driver door speakers. I replaced the head unit from OEM to a panasonic and it was still the same. In looking at the amp, it has independent outputs for the door frame tweeter and the door panel mid/woofer...

Only other thought might be the cabling to the door is bad, but for both? Still looking into it. http://www.automotiveforums.com/vbulletin/#