This just maybe my lack of knowledge on euro cars but i was having problems with my 205 when it started to get a consistant miss all through the rev range at first i thought it was something to do with starvation of fuel as when i held my foot at a position on the throttle it felt like the engine kicked back into life, however when i was taking off one day i heard a small back fire and thought straight away that it could not possibly be starvation but unburnt and low and behold one of my leads was rat shit from residue and so forth so perseded to get a timing light to check the spark and voila no spark so ........there you go ........