In 1. you put a comma after car, and after carefully. The commas delimit the clause.
In 2. you can either put a comma after car, or don't use commas. If you want to make it a defining clause, i.e. "What car? The car that was made carefully in Italy", you don't use a comma. A non-defining clause - doesn't define which car, but just adds information - you put a comma after car.