2004 Chevy Cavalier - Battery Eater!?

[avalonianmoon]

I have a base model 2004 Chevy Cavalier. I bought it brand new at the end of the model year.

I am currently on the 3 or maybe even 4th battery. I just had it replaced Tuesday morning by Valvoline when going in for an oil change because when they tested it, it was reading something 6a left. I had them check the altenator and they said it was fine. I have bad luck with my car dying in the winter, so I had them replace the battery while I was there.

I am concerned that there is something else going on with my car. I've taken it to the dealer previously and they just replaced the battery. I've noticed that my head lights dim when the car is running and I turn on the AC or heater. They some times dim when I put the car in park or drive. I think I've seen them dim while driving or idling behind someone at a traffic light.

What would cause my car to eat through batteries that fast?
the lights do dim when the car is running but they go back up to full strength after a second.
Also, I drive this car daily. Some times multiple times. It is my only car.

 

[rage613]

I would take the car to an independent Mechanic and have them check the alternator output while the car is running also have them check the entire system for a power draw, something as simple as the glove box light staying on, from what you have described I would say that the alternator IS bad.

 

[founck]

Start the car and turn on the headlights. If the headlights dim over time the problem is the alternator, if the headlights stay strong then the problem is your battery.

When they make cars they generally put in the cheapest battery they can, these batteries usually need to be replaced in 2 years or so. The dealer might be putting in low quality batteries as well. If I were you I'd just take my car to an autoparts store such as O'Reilly or Advance autoparts and buy a battery there. If they aren't busy they'll usually install it for you since it just takes about 2 minutes. You'll get a better quality battery there, and it should come with a guarantee that will last for as long as you own the car.