Using Desiccants to Freshen Up the Interior?

A few months ago during a business trip to Hong Kong I made time to meet up with my friend Matthew, who owns and actually drives one of the world's most pristine Nissan Skyline R32 GT-R.  Not only was his car clean and very stock looking on the outside, but the interior was super clean and moreover, smelled new!

Here is a bad photo, taken at night:

Part of that might be these new (gorgeous!) NISMO seat covers he recently installed, but in scrolling through his car build album on his Facebook page, I found that he has also this nifty trick to ensure that the perpetually humid Hong Kong air doesn't cause "stuff" to grow and possibly cause some smells.  Obviously, what separates a clean car from a pristine one (OCD approved) are the details - note clever use of the coat hangar (I'll explain why this is genius down below):

From his Facebook page. Thanks Matthew!

It's currently somewhat rainy in Japan (with its four seasons the country always seems to be raining every 3 months or so, with the change in seasons) and that means lots of humidity (right before summer is the worst though actually).   As I posted earlier, my car has some weird lingering odor, and I THINK (based on the last time I drove it) that the humidity is making it worse. So it is probably a good idea to see if I can eliminate the humidity in the car, especially as driving in the rain means wet footprints left on the car mats.

In Japan, there are many different types of these humidity reducing, desiccant containing products, usually shaped like the ones Matthew used, placed strategically throughout one's residence to keep moisture from building up - e.g. in clothes and linen closets, under sinks, etc.

Here are some of the more popular ones you can find for a few hundred yen each at your neighborhood drugstore or supermarket:

They usually come in packs of three - as they contain calcium salts which absorb water,
the white granular salts get replaced with a liquid.

some versions also contain charcoal 

Others are "flat" types that you stick directly in your clothes drawer,
however these are silica gel based so the hard crystals turn mushy. Not much drying power 

This is what happens at the end -
you have to punch a hole and pour out all of the liquid that's collected before disposing in the trash.
Caution, this is NOT water...

I had actually a long time ago purchased a car specific desiccant product for my GT-R, however running to AutoBacs and paying a premium isn't exactly the smart thing to do. Car specific models tend to be those modified "flat" types or flattened versions of the carbon/calcium salt versions designed not to tip over in a car.

As Matthew figured out, using these desiccant products is key. However, the stuff easily found, while it works well, has a tendency to tip over and possibly spill.  Thus, I was impressed by his genius in using a coat hangar to make a quick and easy custom rack to secure the desiccants around the transmission well.

Inspired, I was going to do the same thing, but then found these:

Super Compact Type! And with 350ml capacity, only 50ml less than those larger box versions!

 The trick of course is to make sure they don't tip over and spill. In my case, I decided to place these under the front seats, as they are flat enough to do so.  And, they are tall enough so that they won't tip over, however I was still concerned that they might end up moving about and ending up in the rear footwell, where someone could knock if over.

Hence, for the time being, I've decided to just stick them under and in front of the front seats.

You can see the all weather mats doing a great job catching all the dirt that would otherwise end up in the carpet!

I will check in a few months to see if moisture accumulation is indeed, a problem. Meanwhile, for 2016 I am planning more serious mods/repairs. Stay tuned...