If it is the factory amp, make sure to check ALL the speakers, especially the left side speakers, one or more may be bad. What happens is one speaker can go bad, and then take out the factory amplifier with it. In hooking up a new amp, it can go bad as soon as you turn it on, if the bad speaker(s) is(are) not dealt with.
I replaced my stock speakers 5 + years ago and they were in pretty poor condition then. Add in the bass-heavy music that is on the air now, it just decreases the lifespan a lot. Those stock 5.25"ers cant handle very much bass, theyre just not designed for it. I'll put my money on the 14 year old speakers. (Psst, Torque...get one of those amps packed up and ready to go, he'll need it too)
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