Tested: Best Car Steam Cleaners

• 3 round detail brushes
• 1 flat scraping tool
• 1 angular concentrator tool
• 1 grout brush
• 1 accessory nozzle

• 1 large mop head
• 1 bristle brush attachment for mop head
• 1 microfiber mop head
• 1 scrubbing mop pad
• 1 jet nozzle
• 1 3-inch scraper
• 1 triangle brush
• 1 large brush for triangle attachment
• 1 round brush
• 1 angled nozzle
• 2 round scrub pads
• 2 nylon utility brushes
• 1 brass utility brush

Not Pictured

• 2 extension wands

• 1 large brass brush
• 1 small brass brush
• 2 large nylon brushes
• 2 small nylon brushes
• 1 jet nozzle
• 1 squeegee
• 1 wallpaper remover
• 1 microfiber pad
• 1 microfiber bonnet
• 1 straight adaptor
• 1 angle adaptor
• 1 mop head

Not Pictured

• Funnel
• O-ring gaskets
• 2 extensions

• 1 steam lance
• 3 microfiber pads
• 1 floor tool
• 1 triangular tool
• 1 window tool (with squeegee)
• 5 nylon brushes
• 1 brass brush
• 1 microfiber cloth
• 1 microfiber bonnet

Not Pictured

• 2 extension tubes

• 1 nylon grout brush
  
• 1 nylon medium-duty brush
• 1 large nylon medium-duty brush
• 1 brass brush
• 1 cotton cover
• 1 microfiber floor pad (installed floor head)
• 1 floor head with triangle brush (which can be separated)
• 1 detail adaptor
• 1 jet nozzle attachment
• 1 detail scraper

Not Pictured:

• 1 funnel
• 1 measuring cup
• 1 mesh bag
• 1 bag of replacement o-ring gaskets
• 2 extension tubes

A car steam cleaner's biggest selling point is its ability to clean without chemicals by shooting super-hot steam at tough messes, loosening them enough to be wiped away with a microfiber cloth. For this test, we wanted to see if each cleaner performed its duty, along with how well it did so.

First, we verified each cleaner's maximum water capacity according to the manufacturer. Once the cleaners were filled to the max, we plugged them into a normal wall outlet and timed how long it took until the cleaner displayed "ready," giving us a time-to-ready measurement.

While doing so, we held the cleaner three inches away from the bucket wall and measured the steam temperature with an infrared temperature gun. We also took detailed notes on the dry weight of each cleaner, ease of use, and other usability observations.

For performance, we ran each car steam cleaner over a section of plastic—such as cupholders, dashboard, and scuff plates. We then tried each one on a seat with Chemical Guys Carpet Cleaner and took notes on how well it removed grime from the fabric. We even tried them on windows and various dirty painted nooks and crannies, like the inner walls of our Odyssey.

Attachments: More attachments mean more versatility. If you plan to use your steam cleaner in the car, garage, and home, you may want to opt for one with multiple attachments of various kinds.

Tank Capacity: A larger tank means less frequent refills, providing longer continuous cleaning sessions. Consider a bigger tank if you plan to use your car steam cleaner for extended periods or don't like refilling and waiting for the tank to repressurize.

Size and Weight: When cleaning tight spaces, the size and weight of the unit matter. If you plan on maneuvering into back seats, cargo bays, and rear floorboards, consider a car steam cleaner that's compact and lightweight.

Hose and Cord Length: Longer hoses and cords provide greater reach, allowing you to clean farther from the wall outlet and deeper into your vehicle without frequently moving the machine.

Temperature: Car steam cleaners vary in temperature capabilities. While basic models may suffice for surface cleaning and agitating tough grime, higher temperatures are needed for thorough sterilization and removing toxins like mold and dust mites.

Heating Time: Car steam cleaners require time to heat water and build up pressure before each use. Factor in this preparation time when planning your cleaning tasks.

Water Type: You should use distilled water to prevent mineral buildup and maintain the steamer's system. Be cautious of extreme temperatures; freezing can damage the unit, so if you live in a seasonal area, remove it from your vehicle or garage during winter.

Storage: Consider where you'll store your car steam cleaner when not in use. Like a vacuum cleaner, your steam cleaner will take up considerable space, so you may want to consider features such as removable hoses, retractable cords, and designated storage for attachments to reduce clutter in your garage or home.

What kind of messes are car steam cleaners good at cleaning?

A car steam cleaner works by loosening up messes thanks to the heat of the steam. Steam can be particularly effective against tricky messes like gum, chocolate, sticky soda, or gooey stains on fabric. Even exterior messes, like caked-on brake dust, can be removed with a steam cleaner.

"I use it on the wheels, I have on calipers, and for very specific cleaning, where you can change the nozzle or the tip," Larry Kosilla of AMMO NYC says. "I call it a 'sniper mode' because you have a lot of pressure and steam at the same time."

What surfaces can I clean with a car steam cleaner?

Cloth, leather, plastic, glass—almost any surface in a vehicle can be cleaned with a car steam cleaner. This makes these versatile machines popular with even professional detailers. However, some detailers, like Kosilla, caution against using them on decals, window tints, and other stuck-on decor such as pinstriping.

Because of the moisture involved, we recommend being careful around electronic components such as the instrument cluster, radio, and climate controls.

How do I clean my cloth seat with a car steam cleaner?

We recommend first spraying your seat down with your favorite interior or carpet cleaner. Then, wrap a microfiber cloth around the nozzle of your hot steam cleaner and secure it with a rubber band or zip-tie. Power on the car steam cleaner and scrub your seats in small sections. You might need a few passes, especially on tougher messes. Note that your seats will be wet from the moisture a steam cleaner puts out, so you won't be able to sit in them for a while.

"If I have something that's very exotic or rare or older,' Kosilla says, "I'm not going to just pour hot water on the carpets [and] seats. You have to introduce heat in another way. And to do that, steam is highly effective."

This is a reminder that car steam cleaners are not upholstery or carpet "cleaners"—they simply blast hot steam to loosen messes that you then need to wipe up. For seats that are stained or carpets that have deep dirt, an upholstery cleaner like Bissell's Little Green might be a better cleaning tool.

Do car steam cleaners sanitize?

As car steam cleaners boil the water, the temperature reaches a minimum of 212 degrees Fahrenheit—enough to produce steam. Steam this hot can indeed kill bacteria, mold, and other organic material on contact. However, as we found in this test, the steam loses temperature rapidly as it exits the cleaner. For these domestic steam cleaners to effectively sanitize, they would have to be very close to the surface you're working on—within an inch or so. There are commercial steam cleaners, which are typically what professional detailers use, that get much hotter than 212 degrees. For the average consumer, the steam cleaners here are fine for normal use on your vehicle—but don't expect complete sanitization.

The Gear Team helps readers make informed purchasing choices about automotive gear, tools, and accessories through hands-on product evaluations and comprehensive testing. Car and Driver's renowned testing standards mandate that we use all products we feature and that our findings and recommendations are based on personal experience and knowledge—not hype. We won't claim to have tested something we haven't, and we'll never recommend a product we wouldn't buy ourselves.

The Gear Team's product selection and gear picks are editorially independent; Car and Driver has a strict policy against accepting payment for placement in articles. We've evaluated dozens of product categories, including floor mats, tire inflators, and car covers.

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