My 155 has recently started to splutter and cough when either at low revs or when my foot is not on the accelerator pedal when driving at speed. For instance if i'm driving along and take my foot off the acccelerator, and then re apply the pedal there will be a lag before it starts to accelerate and it sounds as if the engine is being 'suffocated'. Sounds almost as though I am starting to run out of petrol, although there is plenty of petrol in the car. When the revs are above about 3000rpm there is no problem it seems, but when below is splutters, could this be a problem with the fuel injectors? Also, when the car is at idle sometimes the revs will jump up and down a lot, which led me to believe the idle control valve is playing up.
Has anyone had this problem before or know what it could be? Should I clean the contacts on the ICV and also buy some injector cleaner for the fuel?
Any help would be greatly appreciated.