Hello everyone
Can someone explain to me why the battery on my 94 bonni with 180,000km is discharging overnight when it is parked.

Our 94 did the same thing and it was due to a leak in the strut so the automatic leveler kept running to keep the car level. (I'm overtired and can't think of the technical termilnolgy...sorry)

is the blower motor running when the ignition is off?
is the light in the glovebox shutting off when the glovebox is closed?
are you sure the battery isn't bad?

My 94 is the se model.
It does not have the automatic leveler.
If you think of anything else please let me know
Thanks SSE14U24ME

Thanks for the reply John Deere Boy
I will verify tonight about the light in the glovebox
I know for sure that the blower motor is not running when the ignition is off.
And the battery is the forth one in the last year.
This does not happen everynight.It`* intermitent.
The battery connections were cleaned.
By the way this my 6th alternators in the last 3 years with a new engine
as of august of last year.
I am looking to keep the car a while longer, it drives so well.

Again thank you

Where are you getting your alternators from? Quite a few members have had troubles with units from Autozone (I think thats the store?). If you change your alternator you should also change the battery, a bad battery will kill a good alt and vice versa.

Parasitic Drain will take power from the battery over night, and discharge the battery. You need to isolate some of the suspect loads/accessories by selectively removing their respective fuses while monitoring current flow out of battery. A couple things that come to mind are the power antenna, the rear window defogger. But it could be anything else also. You'll need a DC ammeter, or a clamp on amprobe to monitor current flow. Try to access a good automotive electrician if you can.

Morning
When I wrote " battery discharging " I meant that the battery is
over boiling, it literally leaks from the overflow from the battery top.
Again thi is intermitent. Like yesterday morning there was battery acid on the
ground.Last night parked the car after work and this morning all is clean.
Something is overcharging the battery when it is parked overnight.
Voltage on the battery is always around 12.35 or 12.45
With engine running voltage is around 14.5
The alternator is G.M .AC Delco brand new a month ago .
The battery is from an Auto parts supplier, brand new a month ago.
With all this the car always start. All options work perfectly, even the A.C is still
working like a charm. It has never been touch.
I have been to the G.M. dealer and they are scratching their heads.
Well something needs to be done.
Going back to the dealer monday. They can keep it as long as they wnant.
As long as they find what is overcharging the battery enough to make it leaks.
Thanks for your repplies.

I dont' see how your car can be charging without the alternator spinning.. it might just as well be a bad battery, and since you only got it for a month.. exchange for a new battery under warrenty. If it does it again, exchange it AGAIN.. but at that time you know there'* issues. It might be even a short somewhere.. check your hot positive wires to see it'* not fray anywhere and makin minute short.. not enough to throw everything off.. but enough.. ( i.e 2 strands of wires against the chassis from the hot wire kinda thing )

Wait a minute now, I'm confused. Lead acid batteries don't boil over on discharge. You only get hydrogen gassing while charging a battery & possible boil over if over charging. Your original post describes a discharge condition on the battery. There'* a conflict in terms here.