i need electrical help!

[B-Money]

my 90 laser is giving me hell with these electrical problems! like two months ago i replaced the alternator and my car was perfect again. a few weeks ago my car got stolen and luckly i got it back just like i had it. the steering colum was fine and i was still able to use my key. well i was driving around for like two weeks and i started noticing some of the same problems that i had when the alternator was getting weak on me. the cars automatic seatbelts and window got slower, the head lights are begining to pulse when im at a stop light and there is a power loss and ive been wasting more gas because of it. i just want some ideas on what it could be. my dad is saying its a relay switch or the starter. the car starts fine so i doubt its that. PLEASE help me out, or im going to have no chice but to get a different car.
Thank You
Robert

 

[luv2rallye]

Measure both the DC and AC volts at the battery when idle and not idle and report back. Also when operating power windows.

 

[dmc67]

Where did you get the Alternator from? Advance Auto or Auto Zone? if so then take it off and take it back and have them test it. my car does the samething, and I have been driving it like that for a lil over a yr now. when I'm at a stop light with my turn signal on the lights dim when signal flashes, also when i am runnin bout 4k and let it go down to idle the light's will dim.