My spirit guide tells me this is a 1999 vauxhall vectra, 1.8L (or possibly 2.0L, he's lost his reading glasses again) petrol engine, has not been professionally serviced for 2 years.
You must remove the throttle body and idle control valve, strip them, clean them, pay special attention to the small holes low on the side, re-assemble using a new TB/manifold gasket and all will be well.
Your lucky number is 8, tomorrows weather dull with scattered showers.
mystic megane, September 2009