Removing mildew smell from old car

I'm about to began replacing the interior in my 911 Porsche project. The original interior has been removed down to the bare metal save form some horsehair insulation in the quarter panel area. I really don't want to replace that. But I have a mildew type of smell that I assume comes from moisture at some point. Everything is dry now.

Old 911's as I'm sure you are aware have a bit of a distinct aroma. Mostly a faint smell of engine oil. I don't want to hose it down with something to cover the mildew smell as I don't want to 911 that smells like a bottle of Febreze. I really just want to neutralize the smell rather than cover it up.

Anybody have suggestions for eliminating odors from an old car.?

Bleach water? I got nothing on this one really. Old moparshave a certain smell as well thats impossible to get rid of. I swear its in the steel.

I recently purchased an ozone generator to try on a car that had been heavily smoked in and also smelled of cheap cologne. 

I only did a 1 hour treatment without wiping down any surfaces and it was much better. I imagine with a couple more hours it would have been completely gone. I sold the car before I was able to try it any more. 

https://www.amazon.com/Enerzen-Commercial-Industrial-Deodorizer-Sterilizer/dp/B00JAP7388/ref=sr_1_3?crid=GR4P50EX0PGQ&keywords=ozone+generator&qid=1553626589&s=gateway&sprefix=ozone+ge%2Caps%2C146&sr=8-3

Peroxide or bleach will handle the smell, but will also likely F-up the color in the concentrations you would need.

I would try a carpet shampooer with water and this stuff.  Home Depot SKU 433094:

Home Depot has a product to eliminate moldy odors.  I used it on my house after the Harvey flood.  I had sprayed all my wood with various mold killers but the overall odor was still unpleasant.   The product I bought was similar to the Odo-Ban but more designed for mold odor control - It was called Concrobium Mold Control and was the one that finally killed the odor.

Vinegar in a small bowl, baking soda in another, leave it outside all day with windows cracked, smell should be gone. 

In reply to Ovid_and_Flem :

There is an unscented Febreeze, and as an aside that's how it was sold originally it sell well so they added scent.

Man, stink is hard to get rid of.  Most solutions involve overpowering it with a different stink.  Remove and wash what you can.  Ventilate everything else.

Cut open a fresh apple and put it on a plate and leave it for 24 hours. Do this a couple of times and you should be good. Windows closed 

In reply to Ovid_and_Flem :

Shellac. It seals odor in completely.   

Start with highly diluted ( with denatured alcohol ) 4 parts denatured alcohol to one part of shellac. 

One coat and it will dry in 15 minutes. 

Next coat 2 parts denatured alcohol to one part of shellac. That will take 30 minutes to dry. 

Then one part denatured alcohol to 1 part shellac. That will take  an hour to dry.  

That will seal things properly but you should know that shellac is not waterproof. 

While it will tolerate some water it will not  endure steady immersion.  More than an hour  and it will turn white. Over 24 and it will break down. 

Concrobium Mold Control (thorough clean) + Ozone machine (ran for one hour) = fresh smelling ride!

I've done this in 3-4 cars now and it kills all of the bad smells.

This: Auto Shocker Odor Eliminator

Our e30 project had sat for many years and stank of mildew; we recovered the seats, but carpets, trunk mats, headliner all had the smell baked in deep and long. Used one in the interior, one in the trunk, and it smells absolutely neutral now—thank God, because it’s my car and I have too many allergies to drive a mildewmobile.

If you only need a one-time use and can't justify an ozone generator (or your husband has destroyed his sense of smell and you can't convince him he needs to buy one for all the crappers he drags home), you can spend $20ish on this Chlorine Dioxide vapor generator. Stuff is scary effective.

Margie

Bamboo charcoal bags? I've got four in the Versa. I don't actually know if they work but three different overpowering food smells from passengers didn't last longer than the rides this weekend. 

In the past ive just sprayed a mold destroyer into all the carpets, rolled the windows up and left it in direct sun for a few days

Thanks for all suggestions.  I am fortunate because original seating, carpeting, door cards have been removed and will be replaced with new.  I suspect a good bit may be caming from headline foam backing or dash padding.  

Curtis said:

Peroxide or bleach will handle the smell, but will also likely F-up the color in the concentrations you would need.

I would try a carpet shampooer with water and this stuff.  Home Depot SKU 433094:

Thanks for recommending this product. That's what I do for a living, I'm Technical Director of R&D. If you want to see me make a fool of myself on social media look up our Facebook page and watch the Dave the Chemist videos.

The product works great to eliminate bad odors and control mildew and mold, but it does have a high fragrance load. If you want to keep the Porsche trademark smell, I wouldn't recommend it, honestly.

We've got a new product going to test market in Home Depot stores that's a spray-on odor eliminator that's fragrance free. If you're willing to try it out and tell me how well it works for that application, I can hook you up with some free product. If you're interested PM me.

In reply to ultraclyde :

THANKS! Willing to be your guinea pig and report back.  I'll PM you.

Here's another recommendation for an ozone generator. I used one in my W126 that had sat for 9 years and developed a mouse problem. It took quite a few treatments, but it finally removed the smell. If you do go this route, do not breathe in the ozone. Air out the car before spending any time in it. Trust me.

There’s always some baking soda. Also a product called ozium has always worked for me. Never used it on anything too old or moldy though. 

In reply to Ovid_and_Flem :

If it's the same stuff he sent me last year for my microfiber chair, it should work great. 

RevRico said:

In reply to Ovid_and_Flem :

If it's the same stuff he sent me last year for my microfiber chair, it should work great. 

Hey, I'd forgotten about that! Yep, same stuff. Well, slightly updated formula and now in packaging that is automotive specific. 

Jordan Rimpela said:

Here's another recommendation for an ozone generator. I used one in my W126 that had sat for 9 years and developed a mouse problem. It took quite a few treatments, but it finally removed the smell. If you do go this route, do not breathe in the ozone. Air out the car before spending any time in it. Trust me.

Another ozone generator fan here.  They work great.  I bought my due to old German cars as well.  

In reply to ultraclyde :

Wow!  My package from you arrived yesterday. Way too generous! I'll start beta testing on several projects other than my 911 including my old musty truck. Thanks again!

ultraclyde said:

RevRico said:

In reply to Ovi. 

Hey, I'd forgotten about that! Yep, same stuff. Well, slightly updated formula and now in packaging that is automotive specific. 

Does your magic stuff  get the smell out of  seat springs and stuffing where the mice made a winter home.,..,.they  did not survive !

Not sure this is urban legend or what.....I seem to recall that the odor of death found in a vehicle 

is eliminated with Granny Smiff apples halved or quartered spread throughout the interior for how 

long i'm not sure.....the interwebb awaits..............and no pies thank you very much....