JALOPY
bus, jalopy, heap
(noun) a car that is old and unreliable; “the fenders had fallen off that old bus”
Source: WordNet® 3.1
Etymology
Apparently all dictionaries say that the etymology is unknown. Perhaps from Jalapa, Mexico, to whose scrap yards used cars were often sent from New Orleans starting in the 1920s. First recorded written use in 1924.
Noun
jalopy (plural jalopies)
(US, dated) An old, dilapidated or unpretentious automobile.
(US, dated, slang) A hip, cool, groovy automobile.
Synonyms
• banger, beater, bucket of bolts, clunker, crate, flivver, hooptie, junker, rattletrap, rustbucket, tin Lizzie,lemon
Source: Wiktionary