Alternator - '90 Corsica, 4 cyl.

I've had a whirring noise under the hood for many months now. Sometimes it is much worse than other times. Today it sounded quite constant, and very fast, with few breaks in the shrill noise... I've had a friend tell me it sounded like the alternator. I've also had a shop tell me the problem was the alternator, so I should probably deal with it.

Can an alternator problem occur so slowly (9 months now)? Also, when the alternator goes, will the car just not start one day? or would it die at a red light?

What can I expect to pay for an alternator? Should I get one from the auto wreckers?

Also, is it difficult to replace an alternator? And is it something that someone that knows absolutely nothing about cars would be able to do? Any idea what a shop would charge?

I'm just so tired of car problems and hoping to buy another vehicle before the summer is over. However, I have to make it through the next few months, but things just seem to keep happening with this Corsica of mine. :disappoin

Any advice?

Thanks.

Would be best to remove the belt and then spin the alternator, water pump, power steering pump to see which made the noise. Possible it could even be the belt tensioner. It is possible for the alternator to make noise for a while, as the bearings could be failing. If they do you will get stranded as the alternator most likely will freeze up, your belt will smoke then break. My son had this happen but the alternator broke free again somehow but the belt was really smoking. He made it home and was lucky. I have had alternators freeze up before, twice, and I was not lucky as he was. Now, his water pump was acting up for a while, even though it was not leaking, so I replaced that after removing the belt and checking as I suggested. Sometimes it is hard to guess without removing the belt. If it is the alternator, you can replace it just use caution. There is a single wire going straight to the battery you unhook and one bolt to the alternator. You must unhook the battery before doing this for obvious reasons, or anything else like removing the belt. One our 91 (v6) the bolt can be a slight pain to deal with but not bad. Usually the problem is removing the belt and putting it back on that can cause headaches if you have never dealt with it. The tensioner has to be moved up to relieve tension on the belt. I use a large wrench to hold the tensioner but sometimes you can also get a special tool for this. I think on yours you could do like me, but watch your fingers. There is a belt routing guide on the hood of your car to show you how the belt runs so you can install it. i always install a new belt when doing this since the new one is cheap and is cheap insurance. You could always get a Haynes manual from Advance that can help guide you one this for about 10-12 bucks. Corsicas are rough on alternators. I get about 2-3 years out of a good rebuilt one, but had a good NAPA one fail after a week. A new one is way too expensive, usually over 200 bucks. I rebuilt on can run from 60-100 bucks plus. I get the middle of the road ones for about 70-80 bucks. I would not fool with a used one unless you know it is hardly used(not likely) as I said before, these cars are rough on alternators due to heat and location. Get one with a warranty from a good parts store. Hope this helps, not a real hard job, just have patience and be careful. I cannot be sure but the cost of this by a garage should not exceed an hours work, say 40-60 dollars.