How can the loan company be threatening to take our car back when the first payment isn't due yet??

They can't

Perhaps there was a problem with the down payment? I that happen once.

I would call the dealership there sounds like theres a misunderstanding somewhere along the line

Call the dealership?

How much for a diagnostic test on a 2008 pt cruiser

Sounds like an intentional misunderstanding to me They quoted a price to me on a Enclave that was $361 over the price advertised on their own website. I caught it. They tried to say that they were rounding up. Found the identical vehicle fir $3k less.