Rep Power: 0

I am pretty sure that the battery on my 03 civic is on it's last leg. The light comes on, but it still works and helps a little bit. I decided to pull it apart and check for bad cells, basically checking to see if I could change a few cells and get a little more out of it. All cells were more than 8v and looked ok. Since I don't have the equipment to deep cycle it, I decided to put it back in. Now, I have 165 volts at the terminals when I turn the key on, but it immediately turns off and the ima light is always on. I pulled it out again and double checked to make sure that I had everything together right and didn't find anything. Any help to fix this is appreciated! BTW the car is not worth much, so I won't be dumping much into it.