signs to tell when the alternator is going bad..

[turbo98eclipse]

hey just wondering if this would be a sign that my alternator is going bad:

when i come to a stop, the rpms drop as if the car wants to die..and goes up and drops back again...

and also, while stopped (with lights on), if i rev the engine all the lights in the car will get brighter and when the rpm drops after the rev...the lights go back down (repeat over and over)

so is it time for a new one? what other things should i look for to check? thanx guys!

 

[Benag]

A quick test to do is to clean the terminals. Use the round wire brush if you have one or scrape all around the posts. Also you can pour some coke or pepsi on the terminals and wipe them out really good. Point is to try and get rid of all corrosion. This was my problem when I almost bought a new batt for 70 bucks. Switching to brights would make everything dim out and almost kill it. If this doesn't help just take your batt and alt to autozone for a checkup..

 

[dedlewamp]

A good alternator should be putting out around 14.00 volts at 1000rpm or so. The volts will drop significantly, if the car is almost dieing, like at 500rpm. A alternator that is on the verge of going out will either have very low volts, or abnormally high volts. Like the previous poster said, check all the connections to be sure you have good solid connections everywhere.

The easiest thing to do would be to take it to your local parts store and have them check your charging system. It only takes a few minutes to take off, or you can have them test it on the car.

 

[ndm1]

With the car running unhook the battery and see if it stays running if it does then your alternator more than likely is good.
I had mine tested at a local shop and it tested good but I couldn't find any other problem so I bought a new one and car ran fine after that.