Inside your trunk, there should be over 6 or so small black rubber plugs... over time they dry rot, and with the right amount of pressure from water from ur wheels splashin up, they will fall out, or begin to leak. One thing I did to solve this was use gorillia glue the plugs back in. this last longer. I also used JB Weld on one where a plug had been lost. Also I used a peice of strong blue latex glove with gorillia glue as a temporary seal that has last for over a year. So you can be pretty creative to solve this problem... pretty much its just that rubber seal... if you can replace them more power to you. but to be honest I would prefer feeling them in... if you have any bondo around you can always dab a little bit in and sand it some what smooth, don't have to be to smooth as I assume it will be covered up, and if not, then obviously you don't care if ur trunk looks a little ghetto... I'm not sure how well the bondo would hold but I would think it would work.
If you decide to use JB weld... it tends to fall out of the hole before it drys... so u have to use something to hold it in place until it dries
Fix thanks for the info and I will look at the plugs. However with the amount of water that was in the trunk when I bought the car(discovered water when I got home), I think it must be coming in from up top somewhere. The water was standing in center of trunk where donut tire sits.
I did put some silicone gel around the trunk and did go through car wash and didn't take in any water but I have yet to run it while driving during a heavy down pour. I also read somewhere water comes in by light covers. I will have to do some more searching in trunk and put some water silicone gel anywhere I think problem might occur.
one thing i have noticed on all nissans is the driver side rear tail light seal, i havent been able to fix it but i dont know if you can get the deals or not.....i tried silicone but the sharp angles make small puddles that leak
That could be it... but my trunk seal was perfectly fine... and I had a huge puddle where my spare tire was aswell. so much so it rusted some, and I had to pump the water out... and the dirt left over was horrible!!!!!! Trust me those little holes can do that... spec after a storm... and u hit a puddle or something... or when ur drivein on a wet road... ur tire automaticly splashes up water to the under part of ur car. so little by little that water splashes in, and trust me a few miles on a wet road, with a puddle every now and then can flood the trunk... and im sure u understand water finds the lowest point... hence the spare tire area... Thats normaly the main problem with most nissan sentras of our type... They should be located in ur trunk close to the back fenders.... directly infront of the tail lights... and right behind the "hump" from ur wheel well... little black circles, even if they are intact... they might still leak from dry rottings... I would replace them if I had something better to replace them with anyways... one thing u can do is take a water hose... and spray it on top of ur trunk and in the cracks where the seal is... don't sure jet spray... closest to several differnt kinds of rain... and then check... after that spray it all under the back end of ur car... spec where those rubber seals are... tell me how it goes
I used black silicone on my trunk, just run a bead where the edge of the tail light ( on the top) meets the metal, that should take care of any leak you have, I did mine 4 years ago and it is still dry.