Has anyone ever heard of VATS causing an electrical drain that would cause a battery to go dead after 4 days?

 

No.

Is the fuel pump running all the time? At night, when it's quiet, put ear to hump in rear and listen for fuel pump whine. If it is, replace the Oil Pressure Sending Unit - they can go bad and 'think' there's oil pressure when there's none, and thus they will run the fuel pump regardless of key position or even if there is a key.

 

ok here is another one; do you have a power hatch? when closing the hatch ensure you listen to the motor pull it closed and then you should hear a loud click, else the hatch motor is still engauged and will drain your battery.

 

Only way to check is to disconnect battery , put volt meter (ohms) between power wire and batt + ;
then pull fuses one by one to see which circuit is pulling excess power

 

I too had a small drain but since I don't drive the car much it turned into a dead battery. Today I was doing my checking and found since that I did not close the hatch with the motor(just lowered it till it stayed down) it had a very small drain. .20 milli amp's not much but with not driving much. Checked by putting a digital meter on the neg side and setting to amps and then checked by pulling the fuse for the motor. Hatch up fuse in drain, hatch up fuse out no drain. Hatch down fuse in no drain. Hopefully this is one more fix, but more to come in a 20 year old car