GenVibe - Community for Pontiac Vibe Enthusiasts

Today planned project took a big turn for the worse. Upon removing the interior to clean it, found the front driver floor board rusted through. The bottom sub frame is still intact.

The rust is the thin top metal floor board, the gray in the image is the sub frame / frame rail. Not sure what do at this point, floor pans are probably the worst thing to work on, odd shapes, double layered, hard to stop rust. Guess I will remove what I can, put the driver seat back in and take it in for an estimate.

If the estimate comes comes back high, might JB weld a piece on top of the floor pan. Although welding would be better, I know it would burn off the protective finish and create a bigger rust mess down the road

UPDATE 11/01/15:
Removing the Interior Carpeting
https://www.youtube.com/watch?v=mAVkr4WpqWU
Repair Video Part 1:
https://www.youtube.com/watch?v=eIvwgptIJJ8
Repair Video Part 2:
https://www.youtube.com/watch?v=Mu7a9SKYkZg

Thanks for all the feedback. After I had started the project, I found out their was an epoxy designed for this type of application, eliminating the need for rivets and some metal pre-painting. Link: http://www.nortonautomotive.com/636425-06420.aspx Also, in this case, spilled sugary drinks caused most of the rust, traditional solvents would not remove the sugar. Had to use water with a little soap to get rid of the sugar, then clean the remaining adhesive and residue with traditional solvents.

Derf: I feel bad for you. I know how much work you put into this car fighting rust. I used your informative posts many times.

Maybe it is time to think of your car as a beater, drive it is as long as it will and keep an eye out for a replacement.

Why not have a new piece welded in and recoat it yourself? Maybe with rhino liner or somesuch.

Wow ... that sucks Does this Vibe have a sunroof? Is it possible that a drain line leaked out and water accumulated under the carpeting where no one would notice it? Just a thought. Was the carpeting in such bad shape that when in & out from winter driving that the snow melted and saturated the floor pan? Having said condition happen repeatedly for several years would definitely do some damage as what you now have. I would do something along the lines of what Lannnvouivre suggested. Clean it up as best as possible (sand blasting preferred) then have Line-X or Rhino put a heavy coating directly over this area and up along the rolled edges. This way it would form a permanent "pan" like effect and not allow any future rust to develop.

I would like to weld a new piece in, the layered metal creates an issue. At the factory the Vibe frame was dipped to coat in between the various metal pieces. Once I weld on a new top piece, I would not be able to access the bare metal left from welding, creating a point between panels for rust. Welds in themselves promote rust due to tension and chemical changes left in the metal, which over time causes stress cracks in the finish. Once I get the rusted spot out, will have body shop give some repair ideas.

A great reminder to check under your flooring carpet, just because you take care of the vehicle, does not mean the previous owner did not leave a few surprises. Talking to the previous owner, appears this spot was likely caused by either spilled coffee or tea, with copious amounts of sugar. I can see the spill marks from the console to the driver area. Sunroof was not an issue, no other water damage found, drain lines are working fine. The carpet is dry on top, the factory padding under the carpet acted like a sponge, over the past few years it never totally dried, the sugar acted as a desiccant, soaking up moisture and keeping it against the metal floor. I am sure the Ohio Salt/Brine only added fuel to the fire. These new brine formulations especially with beet juice (sugar), stick to vehicles turning average rust into holes.

So far this is the most significant issue I have encountered, the rest has been normal wear or planned upgrades.

Wow! A spilled sugary drink is the main cause of that damage!

I am glad that I pulled the rug out for cleaning after I bought my Vibe. I think I will also pull the rug out of my son's recently purchased car jsut to make sure there isn't something like this going on.

Maybe the shop can weld in a piece with a significant center hole so that the welds still can be sprayed with paint. Then the center hole may be closed by screwing down a cover.

As long as it is structurally sound, I would:

Clean, scrape, and wire brush it the best you can
Then use something like POR15 [and the metal prep] (they have a small sample kit that would work for you)
Then topcoat that with a spray can of the rubberized spray paint

Because it is on the inside, it shouldn't be recurr unless you park it in a swamp
It may have migrated in between and through to the bottom or will at some point

I'd try to include some kind of easy inspection strip, so you can easily check without pulling any trim. Your floor mat can hid this inspection strip access


I hate when fun projects turn to not-so-fun and possibly expensive ones; good luck to you
I'm fighting a much smaller rust battle on my 2nd gen with 220k from michigan

Doesn't look too bad! If you're sure no water is accumulating there, just apply 2 layers of fiberglass cloth with resin and it's fixed . About $20.00 for fiberglass cloth and a quart of resin w/ hardener from Fleet Farm in Wisconsin. I did this 3 days ago ... just not on my Vibe.

This is what the bottom of the carpet looked like once removed. Their were chunks of rust bonded to the carpet padding Upon pressure washing the carpet, the brown line at the bottom of the carpet was all the coffee/tea that came out. It truly looked like a tea party! Before putting the carpet back in, going to get rid of all the OEM water absorbing padding, and replace it with encapsulated foam. It is a bit stiffer, does not hold moisture, and as a bonus is quieter!

Cut out the worst of the floorboard, now have the Flintstone mobile Checked with calipers, appears to be 20 gauage metal. Indications still point to rusting from top down. In this picture the exposed metal was facing the ground. I pulled back the undercoating to show the holes. Working on way to treat the inside of the subframe before putting the floorpan over top. Thinking I will just make my own drain plug in the top.

Now to finalize plans. Getting two options, goo and pop rivet new oversize panel in place, or cut to size and weld. Both have drawbacks, any ideas or tips?

Talking around, for the given location, decided pop riveting would be the better option. Working the old metal appears their were a variety of factors at play.
-Spilled beverage collecting under carpeting, soaking into fiber padding creating a cycle of rust
-Undercoating that came free or did not seal the joint between the sub frame and floor pan.
-Bad spot weld that rusted through quickly
-Poor metal that was easy to rust
-Stamping that created thin spots in the floor pan

Picture of the patch in place, still have some clean up work and painting to complete.

Floor is finished.... now to reinstall the interior. Posted the repair video and updated notes in the original posting

Working on the carpeting, discovered they put a liner between the carpet and padding. This prevented earlier detection of the rust, plus once the water was in the padding kept it from evaporating. Good at keeping spills on top, but once spills travel below they get trapped.