The little battery light on the left side of the battery guage is coming on. The guage is close to the red zone on the guage. When I have to car in park and put on the gas a little the guage will move up and the light comes off. As soon as my foot is off the gas OR I put on any lights it drops back down to the red zone. The battery is fairly new I believe it is one of those long life batterys. The car starts as usual. Are we looking at an alternator? What is the average cost of replacing an alternator?

Sounds like the alternator. Have it tested. About $150.00 check around.

Sounds like the alternator. Have it tested. About $150.00 check around.

It was the alternator. Had it tested, the mechanic give me a quote 9 ($130 for the alternator plus labor) and the replaced it. When he pulled the alternator he found that the alternator was fairly new. We didn't know this (just bought the car from my father in law). I found the paper work (after our mechanic replaced it) for the alternator my FIL put in and found it was just done on July 5 2007! Our mechanic said to try and take back the pulled alternator to the garage who put it in and get our FIL's money back on it.
My question now is since we took the pulled alternator with us today we were also charged a $70 core fee. Can we get that core fee and the money back for the alternator from my FIL's garage or are we to only expect money back for the alternator? Our Mechanic said that if this other garage are jerks and wont refund anything that we could bring it back to them and they will 'work something out' for us. I assume at the very least the core fee not sure. What can/should we expect the other garage to do to make this right?

Unless you have a guarantee from the first place, nothing.

Unless you have a guarantee from the first place, nothing.
We have the receipt from the other garage. Our mechanic uses the same alternator brand (Remy I believe) he just guessing that the other garage has some kind of warranty on the alternator, one that is supported by the parts manufactorure.