YOU SAID:
A found car is a bad car.
INTO JAPANESE
見つかった車は不良車です。
BACK INTO ENGLISH
The car that was found is defective.
INTO JAPANESE
見つかった車は欠陥車だった。
BACK INTO ENGLISH
The car that was found was defective.
INTO JAPANESE
発見された車は欠陥車だった。
BACK INTO ENGLISH
The car that was discovered was defective.
INTO JAPANESE
発見された車は欠陥車だった。
BACK INTO ENGLISH
The car that was discovered was defective.
That didn't even make that much sense in English.