Define American car? Jaguar, Volvo, Saab, and Astin-Martin are all owned by American companies. Mazda, Isuzu, and Suzuki are mostly controlled by American companies. American companies all have subsidiaries overseas that produce cars for several markets.
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I don’t believe that you’ll find a single car on the planet that has all of its parts made in a single country. Many of the electronics are only produced in SE Asia. At one point, Saturns were roughly 95% American parts, but I believe that number has slipped lately. Besides, all car companies are international, no one is interested exclusively in the American market. There are several big 3 assembly plants in Mexico and Canada, but few parts are actually manufactured there.
I know of Honda, Toyota, Isuzu, Subaru, Mazda, Nissan, M-B off the top of my head. I’m pretty sure Suzuki has a plant in Canada. VW has a plant in Mexico.
Since Chrysler was bought by M-B, forming Daimler-Chrysler, it’s really not an American manufacturer anymore.
Aside from the Daimler, Ford, and GM plants already mentioned being in Mexico (as American companies), and the ones you list, there’s a Nissan plant, and soon to be a Toyota plant.
When we say plants in the general sense, we probably mean “assembly plants” which is where cars come from. But modern car production involves several types of plants. So, there may be a Fiat plant in Mexico that doesn’t build Fiats, but makes Fiat leather seats you could kinda-sorta call Italian. Then, don’t forget all of the suppliers that tag along to build their plants to support the auto plants. Big companies like American Axle and Lear are in Mexico, for example.
There is also a joint venture assembly plant in California (I think in Freemont) that produces Toyota Corollas and Chevy Prisms on THE SAME ASSEMBLY LINES! If you are looking to buy a product that is assembled by American workers you need to look at the sticker of each individual car and take note of the final assembly point and what percentage of the car parts were manufactured in the USA.