I have been having a few problems over the past 7 days or so, with my 4 year old peugeot 307 rapier 1.6. Currently it has 29k on the clock. When I start the engine first thing in the morning the car exhibits some sort of missfire or erratic tic over. At first when the engine starts, the car runs smoothly, but after 20 seconds or so the engine seems to missfire and over revs very slightly to overcome it. This symptom comes and goes whilst the engine is warming up. This problem lasts for about 3 minutes and after that all is well, however if I have been driving for any time and 'say' pull into a petrol garage and fill up, the car will hesitate (after restarting the engine) slightly when pulling away but eventually runs fine thereafter. I have had It serviced 2 months ago, but the plugs and filters were not changed, just the oil and oil filter. Has anybody got any advice as to what the problem could be?, would it be worth my while changing the spark plugs before i book it into a garage for a probable expensive repair bill?. I believe (from the service book) the spark plugs do not need to be replaced for 5 years. Any other ideas would be greatly appreciated. Thanks for the help.