How Nissan creates its own ‘new car smell’

There are a lot of requirements on the materials used inside the car – they have to last for years, they have to be easy to clean, withstand temperature extremes, etc. – so expecting it to smell good is a lot more demanding.

But those tough demands are why automakers hire people like Tori Curl, a materials engineer at Nissan Technical Center in Farmington Hills, Michigan. You oversee a team of scent experts who carefully analyze the scents of everything that goes inside vehicles such as the Nissan Pathfinder SUV and Frontier Pickup. I met her on the show floor at the New York Auto Show to talk about scents and to test my nose.

Curl was originally hired as a plastics engineer, but, in part because plastics make up the majority of the materials inside the non-luxury car, she was soon given overall responsibility for the way Nissan cars smelled inside.

“Every time we launch a vehicle, we have to test its smell,” she said.

While developing a new model, Curl and her team are testing and sniffing individual car parts, such as steering wheels, seat cushions and visors, before putting them in the car to make sure they have a pleasant — or at least harmless — smell.

“Then we put them in the car,” she said. “We sit in the car and make sure we’re in the driver’s seat and you’re sitting in the back seat smelling the good new car.”

Tory Curl scent-tests the components of Nissan cars before they get into the car, and again in a fully assembled car.

The smells in the front seat can be overwhelming Different from the back seat smells. In the front seat, there is a much larger selection of materials near the nose. Besides the leather or cloth seats, there are plastics on the dashboard and whatever make the center console. There are also all bonding materials, threads, and adhesives that hold these things together. In the back seat, you are surrounded by seat material only. There are seats in front of you, behind you, and under you. Then there is the smell of carpet material underfoot.

Even though all of the car’s components, at that point, had been pre-smelled before being fitted into a prototype car, there were still surprises. As with cooking, some scents that are just fine, or even very pleasant, on their own can clump together to create a hellish funk. Or sometimes there was a scent that was somehow overlooked in all the previous sniffs.

Next, Keerl’s team has to begin their investigation. She and her team members are all “certified celebs”. (There is training and certification that includes smell recognition tests that are carefully done.) And they begin their investigations the same way you would try to find a strange smell in your car. They systematically inhale every inch of the car interior until they narrow the source of the odor. Once they narrow down the peculiar smell, they begin the process of discovering exactly which substances or combination of substances is causing it.

A sudden bad smell in a fully assembled car is often because the supplier changed some aspect of how the part was made. In this case, Curl said it will work with the supplier to find what has changed and see if the problem can be fixed.

Because a person’s sense of smell can change over time, even day in and day out, professional scents are regularly re-certified through blind smell tests. They are provided with unlabeled vials of different scents and asked to identify each one.

I tried it myself and it was surprisingly difficult. Smelling the scent without seeing what it comes from is a bit like seeing your child’s first grade teacher in line at the supermarket checkout. You know you’ve met this person before, but without the normal context, you can’t remember where or how.

I opened my first bottle and smelled a rich, mysteriously pleasant scent. Its scent is…earthy. When that word came to my mind, I realized I smelled dirt. It was a box full of soil. The next flask smelled somewhat woody. I failed to realize that I smelled pine shavings, but as soon as Curl told me, I felt a little foolish. Pine must be one of the most recognizable scents in the world, but without being able to see the wood in front of me, I couldn’t quite put it down.

Because attitudes toward scents vary from culture to culture, Keerl’s work focuses on cars intended for North American customers. Car buyers in Europe and Asia may not fully appreciate the scent we find here. They may not like the “new car smell” that Americans appreciate, and would rather have no smell at all.