Age, fuel breather seems fine.
Nat, there's no such thing as a bad idea - and so far wiggling a plug is the cheapest
Skids, stop saying expensive things! But you might be right - it's only happened when the motor gets hot chugging around slowly, tis ok once I get on the open roads and the temp drops a bit.
Think I'll have to hook it up to a diagnostic thingy and throw my credit card at it tho.