Bad battery or parasitic current drain?

[RoadAmerica]

I let my 1989 C4 sit for 3 days as I worked three 12hr shifts at the hospital. I walk to work. I drove the car all weekend and had zero problems. On my day off I went to start the car and it was dead. The central lock had no current and the ding noise never came when I inserted the key. I replaced the battery and now the battery looses a 1/100 of a volt every few seconds. I cannot let my car sit for more than a few hours without starting. The alternator is good. I started pulling fuses to narrow the problem down. Then I disconnected the battery neg terminal and held the meter on the battery posts. The voltage was still dropping. I think the replacement battery is bad. Any help?

[RoadAmerica]

Battery was at 11.56v after sitting all night with neg terminal off. Back to the drawing board. Looks like I'm going to spend some time pulling fuses.

[RoadAmerica]

I pulled all the fuses while the voltage meter was hooked up and nothing stopped the dropping voltage. Whats my next step? Load test battery? Another plug or switch?

[lucittm]

Load test battery. Not unheard of for a new battery to have an internal problem. Unless it meets factory new specs, the seller should replace it for you.

Thanks,
Mark

[CliffBrown]

If the battery is draining while not connected (negative lead disconnected) then I'd make an assumption the battery is defectivce.

You might give it one more chance by trickle charging it for a couple of days then monitor the voltage for a couple more days, it should maintain 12.8 volts.

[RoadAmerica]

After some testing I have found out that it is not the battery. I have found out through some testing that the load on my battery is about 7.8 amps. My mechanic and another master mechanic suspect the alternator is drawing current. They said it can't be a smaller switch or light because the load is too high. I agree, because my car dies in a matter of a couple hours not weeks or days. It's rare but current can actually flow back to the alternator. I guess I will find out Monday or Tuesday. For now I will keep the neg cable off the battery.

[RoadAmerica]

What else could cause a 7.8 amp load? I have an aftermarket Eclipse stereo but I puled that fuse and it didn't stop the current drain.

[lucittm]

7.8 amps is quite a bit of current flow. I would suspect starter or a faulty relay in the front or rear relay panel (thinking AC, heater, misc control module). You pulled all the fuses, you should also pull all the relays. Lastly, it could be diodes or brushes in the alternator. I think that wiring from the battery to the alternator is also on the starter (Terminal 30).

[RoadAmerica]

I pulled all the relays in the front and rear. I pulled one of the connectors under the drivers seat as well. There were two big wiring connectors in the rear fuse box that I didn't disconnect in fear of breaking the plastic clips.