repeat alternator problems

I've got a '97 celica gt. Couple years back my battery light came on and was told the alternator was bad. Having previously been stranded with a dead alternator (in a corolla) after ignoring my battery light, I quickly had it replaced (with an after market). About a year ago the light came on again, I had it tested by two parties and was told it was bad. The shop that installed the first after market replaced it. Yesterday the light came on again and today I was told the alternator was bad again. What gives? I asked if there was anything external to the alternator that could be causing the problem. The battery tested fine and I was told no. I'm considering a toyota alternator but am not convinced that will solve my problem I suspect there is some sort of wiring problem but lack the troubleshooting skills or technical knowledge. My power windows & convertible top have been sluggish since the original alternator problem. I also have idling/starter problems and every now and again the car stalls out several times before finally going.

Any thoughts?

Thanks!

Jeff

There is a high failure rate with rebuilt alternators. You get what you pay for.

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