I replaced the original cassette radio in my '86 with an apparent later model that I bought off Ebay. The new(er) radio has an equalizer and the tape doesn't pop out every time you turn off the ignition. I'm also using an adapter I bought from Circuit City because the new(er) radio has a bunch more connector pins. I also replaced the original speakers because they were in a rather poor condition. Since I'm not a mega watt type, I just bought some cheapie speakers at Walmart.

The radio played fine at first. Then I noticed one speaker stopped producing. Finally, the radio went dead and the display even went blank.

Anyone have any idea what I did wrong? I know in my older car I have to use 10 ohm speakers otherwise it can damage the radio. Is that what happened here?

I would suspect some sort of connection problem, could be at the harness adapter.