ok i lost my key on the vito 108d s reg , i went to merc dealer and they say it has a transponder key ,BUT the key that i lost was not as it was the same as my other vito key ie ; very thin and small and they even said that it is not a transponder key ummmmmmm, the man said strange as on the computor it is a transponder key ,well i came home got the barrle off sorted it to turn and it lights up all the lighs ie: ing,heater , brake lights etc, when i turn it over it trys to start all the time then it will start after about 1 min turning over but it runs like it is on 2 cylinders or running out of fuel it did not do this before i lost the key it was a mint runner any ideas plzz ???