Bought the neighbors 1999 Chevy Lumina. 140,000 miles. All we knew about it was that the alternator was replaced over the last year. The battery drained and we ended up needing to replace the ignition switch (it was letting the key out in aux, thus the drained battery). Then had to get new keys, as the security system was wiped out. We bought a new battery and had the brakes fixed completely. The dealer did the ignition repair and security restart and new keys. Then we had our mechanic fix the brakes and fluids, but while he was doing this he said the battery drained out, and he had to recharge it. So he replaced the battery as well. All is fine, we take it home and drive it that weekend (this is a car for our 16 year old son). We leave it a week and it is dead. The mechanic recharged the (new) battery, did a parasitic draw test, and found nothing. We take it home, drive it on and off for a few more weeks. We find it dead again (battery drained).
Shoule we trash this Lumina. We bought it for $1,700 and have put $1,600 into it.
Nobody buys Luminas for that much. When you get an old car, you want to check the reciepts to make sure that you don’t have to fix things that should have been done by the previous owner. Now that you have it, get rid of the security system if possible and get a fender mounted battery cutoff switch, or just drive it every day. Don’t do any of that, just try to drive it enough to jkeep the battery from going dead.
If the mechanic did the current draw test and found none, it could be something coming on after the engine is shut off. The engine cooling fan can run a few minuets after the engine is shut off; but, it may be coming on later. It shouldn’t. Go to the car, after it’s been shut off for a while, and look for lights and listen for the engine cooling fan, or any motor, running. If the engine cooling fan is suspect, you can replace the engine cooling fan relay and stop that.
You fixed a few things that the prior owner likely had put off. They are done now, so forget about them.
Now you have an ongoing problem with the battery. I don’t thing you should trash an otherwise good car because of a battery issue.
There are several things that the remaining problem could be. It may even be more than one.
I suggest getting rid of that security system if at all possible, especially if it is after market. They seem to cause far more problems than they solve. Other than that, there is the possibility of a battery drain that has not been found (like the fan hellokit suggested) or maybe the battery or charging system is just not working as intended. Just because they have been replaced does not mean they are good.
Remember you now have a car with just one problem. Don’t look back to what else you may have done, it done and over, you now just have the battery problem.
i know you are going to think i am an old fuddy duddy (sic) here with this thought, but…
are you sure your son isn’t sitting out in the car listening to the radio, (loud) just sitting around, not running the car and maybe leaving the lights on thus the dead battery?
it sounds like he doesn’t have his license yet, and may not have learned to shut off the key, (although this may be a lesson)
this may be far fetched, but, since you have eliminated the battery as a problem, then the discharge of the battery through normal means (use) seems likely.