Jimmy's Riviera

My friend has a 1998 Buick Riviera that he bought used and loves. It has 120,000 miles on it. It’s white …

But, has a leak that no one can find. He finds water under the back seat and in the trunk. It is NOT rain water. He leaves the trunk open from time to time to help dry it out cause it smell musty. Can you please help him with some clues ? Thanks

I had an '88 Acura Integra that rusted itself to death. Late in life, it opened a hole somewhere (which I never found). The rear tire(s) would pump water from the road through the hole and fill under the back seat. It sounded like a burbling brook when I took a corner. One very rainy day on a long drive up the Thruway, it pumped enough water in to overflow and flood the rear footwells. I noticed this after the computer (under the passenger seat) flooded and shorted out. It never ran right after that and I ended up dumping the old girl…

It is NOT rain water.

How do you know this??

Thank you. It remains a mystery. He hear’s nothing, just knows where to feel when comes out from under the back seat to the floor in front.