I didnt drive my car for a while. when i went to drive it i bought a new battery. drove it twice and battery was dead. alternator was tested and is good. put a differant battery in this morning started and ran fine. just went out a few minutes ago and the battery was really low. what gould be causing it to drain while the car is off? i disconnected the alarm last week because it had a short someware because the trunk woud pop by itself. but that didnt work.

 

I'm assuming the voltage regulator was also checked...

Put an ammeter between the negative terminal and the negative cable to see how many amps you're pulling. While the ammeter is in, start pulling fuses 1 by 1 until the current drops to normal levels (a couple hundred milli-amps would be acceptable...I haven't checked any of my modern cars...).

 

Get yourself a volt/amp meter.
Dissconnect one side of the battery.
With car off in park place the meter
set to amps, between the hanging cable and the
battery post.
Observe the meter.
I would expect a high reading (>1 amp) for a few
minutes. Then it should drop to less than 0.10 amps.

Let us know what you find.

 

Probably wont have a chance to do work on it anymore till friday or saturday. started it up erlier when i got home just to see if it would start. it starts and runs good until i turn on the headlight s or somthing then the voltage starts going up and down.