(pronounce: aaawww the wise kiko). European (Dutch?) street slang, meaning "the guy who knows it all".
Most probably the word stens from a list of standardized movie characters, like the Smart Kid, the Hot Chick, the Evil Scientist and his Stupid Assistent, the Crook that becomes Righteous et cetera.
Some famous examples of an Oudewijzekiko are Mr Miyagi, Obi-Wan Kenobi and the Indian fellow in Natural Born Killers.
Please look for Wise_Old_Man on wikipedia (links are prohibited here).
Nowadays Oudewijzekiko doesn't exclusively refer to the elderly, but is mostly used as a compliment for a wiseguy, or urbanly speaking: a head.
Wow that's complicated, let's go to the Oudewijzekiko!