These two phrases get used interchangeably, and that is doing a real disservice to what a car perfume actually is. They are not the same category of product, even though they solve a similar surface-level problem.
A car air freshener is built primarily to mask or neutralize odor. The goal is functional: cover up smoke, food, pet smell, whatever is happening in the car, with something stronger. Most traditional fresheners are formulated around that single job, which is why they tend to be simple, single note, and intense enough to overpower whatever they are competing with.
A car perfume starts from a different premise entirely. It is not built to fight a smell. It is built to be a fragrance, the same way a bottle of cologne is a fragrance, with the same layered structure, top notes, heart notes, base notes, and the same standard of ingredient sourcing you would expect from something meant to smell genuinely good on its own merits, not just louder than the alternative.
That distinction shows up in the actual experience. A masking freshener tends to smell fine for a few days and then start to feel synthetic and tired, because it was never designed with depth, just intensity. A true car perfume develops over time the way a fragrance is supposed to, and holds up for weeks instead of days because it is formulated for controlled release rather than a single loud burst.
It also shows up in what people notice. Nobody compliments a car air freshener. Nobody gets in a car and asks what freshener that is. People compliment fragrance the same way they compliment a cologne, because fragrance is designed to be noticed in a good way, not just tolerated.
If your car currently smells like "air freshener," that is a signal in itself. The goal is a car that smells like a fragrance, the kind of thing someone leans in and asks about, not the kind of thing they quietly get used to.