How To Clean Car Carpet From Funk and Stains

Cleaning Car Carpet Interior BMW M3 E92

I’m always complaining that if you don’t eat cheeseburgers in your car, you don’t have to worry about anything other than periodically vacuuming, cleaning your plastics and door panels, and wiping down your interior glass. But, I realized this isn’t exactly true. It’s only a matter of time before Ryan (my son) gets in the car with dirty cleats or Katie Bell (my daughter) spills juice, and I find myself in a situation where all of my talking crap finally will turn around on me, and I’ll have to do some car carpet cleaning.

We have yet to decide on the best-dedicated carpet cleaner solution for OG, but it’s in the works and won’t be long before we have one. We’re also looking into a car detailing steam cleaner and a carpet extractor. These are all things I have on my shortlist to do.

Least Aggressive Method: pH-Neutral Interior Cleaner

For the most part, you can do most of the light carpet cleaning that vacuuming will not get with an interior cleaner, a rinseless wash, a microfiber towel, a carpet and tire brush, and a shop vac. I’ve seen some of the guys here have a thin film of dirt on their fabrics, almost like a brown tint, removed by only vacuuming after a couple of passes. It wasn’t that their car’s interior wasn’t dialed in; they just got in their vehicle with a little bit of dirt or groundwater on their shoes. This kind of stuff happens sometimes, and unlike me, the guys don’t toss out floor mats because of a little crap being on them.

Below are the steps we at OG take to dial in our car’s carpet and upholstery. These methods have worked great for us, but you may decide to make some alterations as you work through cleaning your carpet, which is fine. 

  1. Vacuum the carpets. Before you go and take the visual appearance of your carpet, meaning you need to treat it chemically, vacuum it thoroughly. No matter what, you’ll need to get as much junk as possible out of the carpet to get the most out of the cleaner, so make sure you don’t shortchange this step. It’ll pay off later.

  2. Pre-spray with interior cleaner. Take your interior cleaner; I like P&S Xpress Interior Cleaner undiluted and spray the carpets. For this, I like the spray bottles from Pressol. It’s double action, so every time you pump the trigger, you release a spray, once pulling and once letting go of the trigger. Combine this with the sprayer head's nice, atomized spray pattern, and this spray bottle is legit.

    When you spray, you want a nice, light coat on the carpet. You don’t want to get the carpet soaked. It’ll just make it harder to dry or more work to vacuum later. You want just enough to get even coverage.

  3. Use a carpet and tire brush to agitate. Immediately after you spray the carpet or the floor mat, begin to brush aggressively. If you already have a fabric and tire brush, you can re-use it; just make sure to thoroughly rinse the chemicals before using the brush on the fabric.

    I want a separate brush that I will use for just carpets and upholstery. The tire brushes tend to get a little dirty over time because they are being used on the tires, and even when they get cleaned, they tend to have a little dark residue left behind.

    If you choose to use P&S Xpress Interior, it will foam a fair bit. The foam may or not change colors, depending on the level of dirt on your carpet. Just make sure you scrub the entirety of the spot you want to clean.

  4. Follow with a second vacuum. Now, go right into vacuuming the carpets. As long as the cleaner has 2-5 minutes of contact time (I would lean towards 5), it’ll do the job—vacuum as much of the cleaner as possible. The more you get out, the less chance you have of the surfactants and cleaning agents in Xpress (even though it is pH neutral) from pulling junk from your shoes and clothes.

  5. Finish with rinseless as a neutralizer. To help finish up the neutralizing, I like to use a rinseless wash (I prefer McKee’s N-914). I use this diluted 1:256 here. I also like to spray a fair amount with this solution but not oversaturate it. After I get full coverage, I simply mop up with an interior microfiber towel.

    Allow the mats to dry (as much as possible) before re-installing them, or if it is on a section of the interior that can't be easily removed, like a seat or the carpet itself, simply leave the vehicle doors open as long as possible. This also adds a dark, rich look to the fabric it’s put on without leaving a sheen.

    Pro Tip: Using a rinseless wash as a dusting agent on plastics or leather will also make them look vibrant while still leaving them matte.

  6. Medium-duty cleaning method: All-purpose cleaner light dilution. If the pH-neutral interior cleaner isn’t removing the dirt, use an all-purpose cleaner at a light-strength dilution to remove it. I selected Koch-Chemie Green Star as my all-purpose cleaner of choice. For Green Star, Koch-Chemie recommends a dilution of 1:10 to 1:20 for fabrics.

    You’ll want to start at the lightest dilution possible for the intended use, so I would try 1:20 first. Before I even start using the APC, I would want to wait until all fabric is completely dry before I move on. I also would give it a final vacuum to see if that will remove the remainder of the soiled spot.

    Follow the same processes for the interior cleaner here. The process doesn’t change; just the cleaning chemical does.

  7. Heavy Soil Removal: Pressure Washer or Steamer after agitating with All-Purpose Cleaner. If medium-duty cleaning still fails, you’ll need heat and/or pressure to remove the stain. Once again, you want to wait until the carpet is completely dry and give it one final vacuum before you move to this method.

    Keep in mind that if your floor mats look like they are not structurally sound, do not use a pressure washer. If your carpet almost looks flaky, dried out, or you seem to pull up small chunks of carpet while vacuuming, do not use a pressure washer or heavy dilution all-purpose cleaner to clean your carpet. This will be a rare occurrence; if your car was made in the last ten years, I can almost guarantee this sn’t the case. This deterioration usually happens to older cars; we’re talking 20+ years old. Most of you will not have to worry about this.

Porsche GT3RS Interior

If you went through the steps again and you’re ready to move on, you can use a pressure washer on the floor mats after the all-purpose cleaner or a steamer on fabrics.

After agitating with the APC, take the mats and thoroughly rinse with the electric pressure washer. You want to move top to bottom with the pressure washer, keeping the pressure washer about 8-12 inches away from the mat. It will also be helpful if you perform this process using mat holders. That way, the dirt will want to remove itself from the mat and fall on the ground. 

These mat holders also make vacuuming much easier, and you don’t have to spend much time bent over your car or the floor.

After you finish with the rinse or on other fabrics, it would be helpful to do a vacuum to help dry the mats. 

Follow that up with the final spray of rinseless solution as a neutralizer. Make sure to leave the mats out of the car or the doors of the vehicle open until everything is dry to prevent a mildew smell or a film on your interior.