You are partially correct in that the second character Kou means mouth.
KeKou means tasty or palatable
Kele can be made out as happy or joyful
All together it comes across as a ‘joyful or happy taste in your mouth’
I got the explanation from my Chinese prof in the late 80s and then heard the story again in a couple of biz school marketing classes. (The counterpoint was the Chevy Nova in Latin America - Nova translates no go)
Here’s a nice link that sums it up: http://csymbol.com/chinese/chinese_branding.html
However, I still think that it is the 1st and 2nd characters from the left that are ko--they are the ones shaped like a mouth.
The nova story is urban legend
Indeed, as far as anyone (including myth debunker Snopes.com) can tell, this Nova blunder never occurred. No record exists of a campaign to sell Novas in any Latin American country and, even if the alleged campaign had existed, it probably would not have flopped due to its moniker. “Nova,” a single word, actually means the same thing in Spanish as it does in English and is a reference to stars, not an object’s ability to move. In fact, for years, the Mexican government-owned petroleum company Pemex sold gasoline under the brand name Nova, and the name did not cause any problems for them.
The Chevy Nova is not the only urban legend spread throughout international marketing circles. Like the childhood game of telephone, which illustrates the errors created when tales are passed down the line, many international marketers and journalists have inadvertently shared similarly debunked anecdotes. When I first heard the Chevy Nova story and others like it, I also repeated them several times before others corrected me. Fortunately, true stories can illustrate the same global branding lessons.