Can anyone give me any advice on how to go about changing the MAP sensor on my 1998cc Peugeot 406 coupe? I have had an engine "juddering" issue that has gradually got worse and eventually activated the engine warning light. I had the engine management unit decoded and it said "254 - MAP sensor". A "10 mixture error" was also reported that the man in the garage said often accompanied a MAP sensor failure. I was also told that MAP sensor failures were quite common on 406s. My Haynes manual says that the MAP sensor is mounted on the inlet manifold and removal/replacement is described in just 3 sentences. Should be easy - eh? I just can't see how to get to the sensor without either having an arm with six joints or to remove the exhaust manifold to get at all the bits underneath. In any case, I don't think that I can see the sensor. Is there some easy way to change the sensor that I haven't spotted? Many thanks if anyone who has solved this problem can reply. Mike H.