Lumpy Idle

[Nelly1979J]

Hi all, I currently have a problem with my 51 plate 2.3 Zetec Galaxy. When the engine is cold when you pull away you get a lack of power followed by a surge, this can sometimes show itself as quite a lumpy idle. I changed the spark plugs, and have ordered some leads and a coil pack. The problem doesn't seem as bad now since having new plugs but something tells me that this may be a red herring, it just seems strange that once the engine is upto temp it doesn't happen again. Could this be a Lambda sensor on its way out or even the MAS or do you think my original diagnosis of something in the ignition system, plugs, leads or coil pack is to blame?

Thanks in advance.