I had a 205 which had a leak in the manifold part of the exhaust which made her cut out ( this was caused by no gasket between the two connections so it was blowing just enough to make it cut out)
If not
I have a vauxhall vectra(never buy one, piece of p*ss)and it has problems and revs when the idle and idle sensor are dirty(can't particularly see the dirt) gave the parts a really good clean with carb cleaner and not a problem since( a problem which vauxhall couldn't pick up so they decided to rewire my cambelt sensor instead, bunch of tw*ts !)
hope it helps you out
shelly
March 2006