Hi every 1 sorry if this is in the from place I have a c200 cdi sport 10 plate the engine light was on and of for a few days then stayed on so took it to a mate to plug in comes back with DPF blocked no other codes so booked it in to get a terra dpf clean week later fella plugs it in on the day comes back with dpf and bank 1 lamber sencor as well plus a reading of 30 psi witch was very high so he said to get Merc to plug it in as I could be wasting my money on the dpf clean of if it needs the lamba and a air/ pressure sencor Now every 1 I have spoke to have said the lamba sencor will come on if the dpf is blocked ?? So was thinking get the dpf clean / unblock done and get him to reset all the codes and go from there Merc want £170 to just plug in clean in £200/£250 so fort try that or am I wasting my money sorry for the long post any help at all will be grateful thanks