Couple of Problems

My 03 Max is making this rattling noise when I drive. I think it is between 2K and 3K RPMs. It has been doing it for awhile. Sometimes it goes away for like a couple of weeks and then it comes back. I changed my oil today to see if that would make a difference... Nope. What could this be?

Another question: I definitely have a leak in my trunk because my spare tire well gets water in there? How do I fix that? How do I find the leak?

My 03 Max is making this rattling noise when I drive. I think it is between 2K and 3K RPMs. It has been doing it for awhile. Sometimes it goes away for like a couple of weeks and then it comes back. I changed my oil today to see if that would make a difference... Nope. What could this be?

Another question: I definitely have a leak in my trunk because my spare tire well gets water in there? How do I fix that? How do I find the leak?

Mileage?

It may be loose rear license plate or front grille. Or smtg between... In other words, please describe more detailly: noise direction, does it vary (how), accel/decel/coast only etcetc. Typical "rattle" source is exhaust, its loose supports and/or shields.

First check upper trunk seal. Maybe not seated well, dirt/ice whatever guiding rainwater in? Rear window seal?
Seek: Take used newspapers and place under mattress all around, check daily. Where papers starts to wet, leak source is in that direction. Expand 'papering' until the spot becomes clear.