Rust on Mazda Miata

I live in Michigan and my Mazda that I drive year round is rusting badly. Can fiberglass cover rust where a hole has been eaten through? How expensive is any repair. The rust is around all four wheel wells. Thanks.

The rust that you can SEE is around all 4 wheel wells, if you get the car up on a lift you will also see rusted fuel and brake lines,floor pans, frame etc. If you have a metal fuel tank that will be rusted also. On Chrysler minivans I have also seen rust ruin a plastic gas tank by having the locking ring (metal) Have a buildup of rust under them so bad that it outs holes in the plastic threads of the gas tank. I have also had rust cause a spare tire fall off by eating through the cable that held it on. Also had I rear emergency brake spin a car around when the left rear trailing arm decided to part ways with the car due to rust. And ow they are adding compounds to the road salt that attack the steel on your car even faster. Fiberglass can cover up the rust for a year, maybe 2.but with the cost of painting today I doubt if it is worth it.
You don’t say what year your Miata is but if it is new enough there may be some warranty coverage.
These were not really designed to be a winter car.

It’s not worth it; and the car needs to be inspected to verify whether or not it’s even safe to drive.

Fiberglassing the rust will just cause it to rust under the fiberglass so it is like putting a band aid on a bullet wound. Eventually, it will just come back.
If it needs to be repaired, it has to be done by welding in metal.

I agree with @RemcoW, the metal under the fiberglass will just rust away and the patch will fall out. Cut away the cancer, weld in new metal. This is NOT cheap and you WILL find more rust like @oldtimer 11 says. It may be superficial holes through the body which means you can still drive it. Have someone put it on a lift and see if 1) It just folds in half right there (bad) 2) has rust near suspension, spring and shock mounting points (really bad, it could fail w/o warning) or 3) rust near the transmission or differential mountings (bad, too). If you can poke a screwdriver through anything underneath, start planning to scrap this out and get a newer car.

There are so many Miatas out there, you’d be way better off to just take any money you’d spend fixing your car and just buying a newer rust free one.

bottom line, not worth the money or effort.

If you car has rusted area limited to wheel wells and doors, you can get metal breed in but I would not fiberglass dissimilar materials. The next Mazda i suggest you do research on rust preventing strategies you can do to your own cars. If you are Willing get dirty once a year, you can keep a car rust free on areas you treat for decades.

You need a vacation. Head on South, to Texas maybe, and buy yourself a new (used) MIata. Just shop in Craigslist for the cities you might visit. Somewhere there’s a rust free Miata waiting for you.