well not rough but seems to idle ok(ish) when cold. However when you shut door or shut boot revs dip then rise.

 

Does this sound like an electrical problem ie bad earth or loose/split hose or something.

 

Ive had a rummage round under bonnet while engine is cold and ticking over but cant move anything that seems to make it drop/rise again.

 

anyone else had this?

try pressing the interior light switch in the door slam and see if that makes the revs irratic

nope, just seems to be when door bangs.

i had something similar could be a vacum leak nightmare to find, i pulled the vacum pipe off the balance pipe by the brake master cylinder they go to your aiv valve solenoid, and put my thumb over the balance pipe hole hey presto found the problem, my brother got pissed off though with me driving around and him squezed under the bonnet with his thumb over the pipe though LOL!!!

could be a loose tps maybe ?? worth checking as a slight knock can alter the voltage if its not tightened up.