My battery drained completely out the other night, my fault. But now it starts real weak, idles rough, and red lines for a excessive amount of time before shifting. And since the rpms are climbing so night for so long my millage it's trashed. I just want to know if this just the battery and not the alternator, or transmission. Because if I go buy a new battery and I'm still having problems I'm not gonna be happy haha

 

The battery should be tested before replacement. Draining a battery is hard on them. it may be ruined, particularly if it is several years old. If it is over five years old, replacement is probably wise, but then testing is the only way to know. Replacing parts for no good reason is a waste of money.

How did you charge it back up?

It's important not to use a defective battery in that they can cause damage to the charging system (the opposite is also true)

 

Have a qualified shop test it.

This spring I dragged my wife's Miata out of storage at my friend's garage. Last year I replaced the 'midget' battery with a full size unit. Long story short my wife was having problems with the new battery not staying charged. She took it to a local 'auto center' three times and every time they told her the battery tested OK it just needed a charge. The truth was the battery discharged over last winter and it froze, cracked and leaked out 90% of the electrolyte! That shop never saw the big *ss crack on the corner of the battery!!!

 

I have an 06 Miata with a Red Top, and it stays on a battery tender all the time. Many 'Vettes have the same requirement. I believe its a sports car thing...