I noticed any time it rained hard I would get water running across the floor. Where our pod is parked on the driveway it is tilted slightly so the driver side is higher. I discovered the water was coming in from around the fridge, hitting the floor and then running all over the place. Taking the fridge vents off left me mystified because it was almost completely dry inside. I finally figured out that the caulk on the lower vent had failed along the forward edge, allowing water to wick in and then down the inside of the outer wall - completely bypassing the fridge compartment. I had a tube of white vinyl caulk on-hand so I took the frame completely out, removed as much of the old caulk as I could, and applied new caulk... liberally. I added more caulk just inside the frame along the bottom edge, too.
So take note and if you have an "older" pod, double-check behind the edge of the fridge vent frames. They may look ok at first glance but you need to pull on them slightly to be sure.
Oh, and it rained hard last night so I checked inside on my way to work this morning. No water, yay!