It's a bummer / it's a trap
Comprar carro usado sem garantia é fria.
Buying a used car with no warranty is a trap.
20th-century Carioca/Paulista slang. Frio = cold, and a fria is an unpleasant or deceptive situation. The metaphor is the unwelcome chill of a bad surprise.
Falando's Idiom Trainer teaches you to recognize idiom meanings and create sentences using them, so you can speak like a Brazilian.