Idle speed wayyy to high! 2500rpm!!

ive got a 1982 karmann golf cabrio.

it revs really high when it idles, does any one know what might be the problem?   

ive tried ajusting the settings on the carb,   but no joy. :dontknow:

Plzzz help, thnx

Air leak on the inlet side ? Vacuum pipe fallen off ?