The name Coca-Cola in China was first rendered as Ke-kou-ke-la. Unfortunately, the Coke company did not discover until after thousands of signs had been printed that the phrase means "bite the wax tadpole" or "female horse stuffed with wax" depending on the dialect. Coke then researched 40,000 Chinese characters and found a close phonetic equivalent, "ko-kou-ko-le," which can be loosely translated as "happiness in the mouth."
In Taiwan, the translation of the Pepsi slogan "Come alive with the Pepsi Generation" came out as "Pepsi will bring your ancestors back from the dead."
Also in Chinese, the Kentucky Fried Chicken slogan "finger-lickin' good" came out as "eat your fingers off."
The American slogan for Salem cigarettes, "Salem - Feeling Free," got translated in the Japanese market into "When smoking Salem, you feel so refreshed that your mind seems to be free and empty."
When General Motors introduced the Chevy Nova in South America, it was apparently unaware that "no va" means "it won't go." After the company figured out why it wasn't selling any cars, it renamed the car in its Spanish markets to the Caribe.
When Parker Pen marketed a ballpoint pen in Mexico, its ads were supposed to say "It won't leak in your pocket and embarrass you." However, the company mistakenly thought the spanish word "embarazar" meant embarrass. Instead the ads said that "It wont leak in your pocket and make you pregnant."
An American t-shirt maker in Miami printed shirts for the spanish market which promoted the Pope's visit. Instead of the desired "I Saw the Pope" in Spanish, the shirts proclaimed "I Saw the Potato."
Colgate introduced a toothpaste in France called Cue, the name of a notorious porno magazine.
In Italy, a campaign for Schweppes Tonic Water translated the name into Schweppes Toilet Water.