Shelby

why after 3 or 4 plus days, a 1996 ford crown vic will not start. have replaced alternator, curtosey of the ford dealer. PLEASE HELP

Have someone check if there’s a parasitic current draw on the battery as the vehicle sits.

Tester

Maybe you need a new battery?

I recall a similar “mysterious” problem with a Lincoln parked on a steeply sloping driveway. In that case, the trunk light switch (a mercury filled switch) was defective. On the level it was off, but on a slope it made contact and the trunk light drained the battery.

Agree that there should be a thorough check for parasitic drains.