Bio:  Prentice St. Clair, CD-SV, RIT has been providing training and consulting for the professional automotive detailing industry since 1999, as well as detailing services to the motoring public many more years than that.  Prentice holds many certifications within the detailing industry, and is a Recognized Industry Trainer through the International Detailing Association.  Considered one of the industry’s leading experts, Prentice has been inducted to the IDA Detailer’s Hall of Fame.

The interior of your car is where you spend perhaps as much time “indoors” as you do your home.  Those who like to have a clean home likely enjoy a clean vehicle interior as well.  Interior care involves cleaning, protecting, and deodorizing.  Let’s talk about how to keep your vehicle interior looking great using the Proje’ Intensive Process for interiors!

In the post “Interior Care Primer:  Part I”, we looked at the important first step of vacuuming, followed by headliner care, and finished up with the vinyl and plastic surfaces like the dash, center console, and door panels.  Next we’re going to jump in with both feet on seat care.

Leather Seats

To start, it is important to understand that the term “leather” is now used for an assortment of seat upholstery treatments that appear or feel like genuine leather but are not necessarily natural cowhide.  For example, “vegan leather”, Leatherette, and Pleather are all man-made materials, typically a form of vinyl.  You do not have to be an upholstery expert, however, to properly care for your “leather” seats, whatever material they may be.

True cowhide leather is dyed in a color that goes along with the interior color scheme of your vehicle.  Understand, however, that the “dye” is actually sprayed on the tanned surface of the cowhide, and then often top coated with a layer of clear paint.  Now, this sounds similar to the concept of the exterior basecoat-clearcoat paint system that is used on most production vehicles, but the paint used to coat the leather is specially designed to be super-flexible and very durable against the wear-and-tear of passengers getting in and out of the car and sitting for long periods.

And, as some of you have experienced, natural leather coating can wear off or be scuffed with heavy use.  Also, natural leather dye, while starting as a complete seal between the environment and the foam seat backing, begins to micro-crack with months and years of use.  Thus, it is necessary to use the appropriate cleaners and conditioners that will not damage the collogen layers beneath the dye layer, as well as not removing dye.

That’s admittedly a lot of background information that leads to this simple solution for natural leather care . . . for cleaning, use Proje’s Alpha Interior Cleaner, using the same technique described above for cleaning plastic and vinyl panels.  For conditioning leather, use Proje’s Plush Leather Conditioner, which is a non-greasy formulation with UV protectants.

You can mist the Plush Leather directly onto the leather seats, then blend in with a RedPRO Micro Fiber Towel.  Or, if you are concerned about overspray, you can spray Plush Leather onto an applicator pad like Proje’s Blue Applicator Pad, and then rub it into the leather seats.  Although Plush Leather is a non-greasy formulation, I recommend following up with a clean interior micro fiber towel to buff off the excess conditioner, leaving a satin finish that does not feel slippery, makes the leather look and feel new, and keeps it protected from UV rays.  Plush Leather also slows re-soiling of the leather with its stain guard ingredients.

The process just described will be safe to use on all other forms of seat upholstery that are labelled by the vehicle manufacturer as some form of “leather”, including vegan, faux, pleather, and even straight-on vinyl upholstery.

Fabric Seats

Fabric seats, especially “sport cloth”, can be challenging to clean when stained.  That’s where Proje’s Upholstery & Fabric Cleaner comes in.  The seats by misting with Proje’s Upholstery and Fabric Cleaner.  For better results, let the cleaner dwell for a couple of minutes.  Then scrub briskly with our Carpet and Upholstery brush.  Finally, wipe with one or more clean RedPRO Micro Fiber towels to remove the loosened soil and excess chemicals.

Professionals will use a hot water extraction machine or a steam machine instead of a damp towel.  Certainly, if you have a consumer version of this equipment, it will help to extract the soil that has been loosened by the cleaner, as well as removing the excess chemical.  Removing as much of the chemical as possible is necessary to help reduce the re-soiling of the area.

One of the challenges with fabric upholstery is in its typical construction.  The fabric surface that you see and feel is essentially a thin layer of material that is covering the custom-shaped foam bolsters that make the shape of the seat.  This foam material acts like a sponge when liquids are spilled onto the seat.  The spilled liquid simply soaks through the fabric and into the foam backing.  By the same token using too much cleaner or water to rinse the seats will also soak the foam backing.  Thus, with cleaning fabric upholstery, the less liquid introduced, the better.

One of the added benefits of Proje’s Upholstery and Fabric Cleaner is that it contains odor neutralizing enzymes that actually kill any remaining odor-producing micro-organisms.  And with its pleasant scent, it’s a one-two punch that leaves your fabric seats smelling fresh and clean.

Carpet Care

If the carpeted mats need complete cleaning, they should be removed and cleaned first, so that they can dry in the sun as you work on the rest of the interior.  If the mats require only spot cleaning, this can be performed with the mats left in place, but perform this step after taking care of everything else inside the car so that the cleaned spots do not become re-soiled as you work on the rest of the interior project.  Similarly, rubber or vinyl mats should be cleaned last, and we’ll talk about how to do that later in the article.

Clean the removed mats using the same techniques described in the “Fabric Seats” section.  Basically, mist the carpets with Proje’s Upholstery and Fabric Cleaner, scrub with our Carpet and Upholstery brush, and wipe with a clean RedPRO Micro Fiber Towel.

The remainder of the carpeting inside the car can be spot-cleaned or fully cleaned as needed using the same procedures.

This is important!  When replacing the floor mats, make sure to connect any safety clips that keep the mats place.  If unsure about how to properly secure the mats, check the owner’s manual in your vehicle.

Vinyl and Rubber Mats

Vinyl or rubber mats can be cleaned in place or removed from the vehicle for cleaning.  Spray them liberally with Proje’s Alpha Interior Cleaner.  Let the chemical dwell for a minute or two, then scrub with Proje’s Carpet and Upholstery Brush.  If working inside the car, wipe away the chemical residue and loosened soil with our RedPRO Microfiber towel.  If removing the mats from the car for cleaning, you can rinse the chemicals and soil with a hose (onto your lawn!  Save the water).  Dry in the sun.

As bad as the vinyl mats may look after cleaning—dull and scuffed—resist the temptation to spray or wipe them with any kind of dressing.  The dressing will make the mats slick, and this is especially dangerous for the driver, whose shoes could slip off the accelerator or brake pedal if they are coated in dressing from the mats.

As mentioned earlier, when replacing the floor mats, make sure to connect any safety clips that keep the mats place.  If unsure about how to properly secure the mats, check the owner’s manual in your vehicle.


Well, there are a lot of different surfaces inside the vehicle, and, as you can see by the discussion so far, each one must be cared for with specific products and techniques.  In Part III of the “Interior Care Primer” series, we’ll move onto the next steps in the interior detailing process, which is window cleaning and interior dressing.