aight so my car doesn't want to start sometimes...
i've change my starter and battery, and the previous owner said he change the altenator...
do you guys thing my alternator might be bad..

 

Very vague.... more details. Have you done a tune up? Any codes?

 

I bet you could be more vague, but I'm really not sure how.

Is the starter motor turning the engine over, and it's just not firing up? Or are you just getting nothing at all or maybe just a click?

edited: ok re-read your post, I'm assuming you mean your battery is going dead. Assuming you're not getting the idiot light, then your alternator is probably ok. You could pull it and get it tested at any autozone/advance etc, but I doubt that's your problem. Check each circuit at the fusebox for a current draw if you're so equipped. You might have something shorting out and killing your battery.

When you replaced the starter, did you get the starter/solenoid as a unit?