Originally Posted by gearbox
best way is get in the trunk with a flashlight and have someone hose the car from different places.
Sounds like something the CIA would do to you, that or a horror story
Anyways, If you're leaking that much, I doubt it's the spoiler holes, you might have a huge crack/break in the weatherstripping of the trunk, that's my best guess.
OR, in our 7th gens, theres a trunk vent flap. Not sure if they have that in the 8th gens, but if that vent is missing, might explain a lot of water going into your car while driving.