1990 Olds CC with water in middle seat passenger footwell

I have a 1990 Boxy Custom Cruiser with water wicking through the carpet at the back edge of the passenger side second seat footwell. It had sat outside during a rainstorm at the shop last November for a week before we covered it. When it came home both the front and rear passenger side footwells were saturated. At first, I thought it was because a shop put our car cover on the back seat wet but strangely the seat itself wasn't wet. After using heaters, a dehumidifier, and a carpet cleaner I was able to dry it up completely over the course of a week. The last stubborn spot was the same exact spot where it has returned. It's been driven and parked in the rain a few times over the last two weeks but the front floors and driver's side rear floor are still bone dry right now. Only that one spot is wet! It normally lives under a carport so it doesn't normally sit in the rain. The way I discovered it this time was by lifting the floormat to clean and I noticed the back edge was wet. I've even been under the car probing for leaks with a light but the floor pans look mint and super clean. It's definitely water, no sweet smell or loss of coolant. Just smells like dirty carpet water when you press with a paper towel.

Anybody else run into a leak in this spot? Any ideas would really help my search.

On my 87 Pontiac Safari wagon I have had an issue with the third row foot well being soaked on occasions when the car was left outside, also have found water in the spare tire well, and it looks like the water is coming in from the side window, I also have found a small leak on the passenger side of the windshield, so you might pull off the trim around the wheel well and watch while someone outside is spraying the car down in that area.

My window guy sealed the rear of the passenger quarter glass to stop a spare tire well leak. I was also thinking it could be the front side of that glass. It would be easy for it to follow the wheel well into that floor.

Read this post, it was my problem and Mike's. My floor was wet in the front passenger side and traveled to the rear.

https://www.impalassforum.com/threads/rain-water-leak-inside-front-firewall-recent-winshield.236840/

Good luck

Tom

Tom, you may be right. The water showed back up in the front carpet after heavy rain. While exploring under the hood I've discovered that during a previous heater core replacement they did a crappy job of sealing the heater/AC box to the firewall. It has cracked and missing sealant at the firewall. Could it be possible because of the rearward rake of the car that the water is running under the carpet pad to the back floor and then building through the carpet the more it leaks? I can't see water trails down the metal under the dash but it is dampest along the outboard edge of the well in the front and the back outboard corner of the rear well. I also pulled the side panels out and found no evidence of leaks from the front corner of the quarter glass.

If I remember correctly, i removed at least the passenger seat and peeled back the carpet. I may have removed t all the seats and the carpet. Then I stuck a hose down where the cowl is. It poured in, I found the leak! Have someone give you a hand with the hose so you can watch where it is coming in. Water finds paths that you wouldn't think would be possible.

You're getting close to finding it, stick with it.

Tom

Today my son and I got the front carpet, front and rear door sills, glove box, kick panel, and passenger side trim panels out today. Quite a bit of surface rust spots and water in the jute pad and on the metal. The feet of the seat has tons of surface rust.  We used and hose and put water to the heater box, doors, and underbody.  After almost giving up, as I'm about to back the wagon back in the car port suddenly water appeared on the front floor. It appears to be coming from an opening between the intersection of the floor pan, firewall, and fender in the lower right corner.  Pouring straight down the side along the sill and ending in the floor pan channels and making to the back floor also.  By the look of it, it's been happening for a long time.  Has anyone seen this and how did you fix it?  I have inserted some photos.  In the photos it appears to go out the door but with the sill in it pushes it under the carpet.url=https://servimg.com/view/20020905/29][/url]

It was the passenger cowl drain by the fender. It was clogged with mud and pollen pods and was coming in a pin hole in the footwell seam. I sealed the seam at the front of the footwell where it meets the firewall and cleaned the drain on the outside and it appears to have stopped leaking. We have washed the car and it rained and no new water. Now I need to lift the seat out and pull the jute pad to replace it and Por-15 the floor pan were it has surface rust from the leak.