Hi, I’ve spent 2 days testing and searching on the web and haven’t been able to find an answer and I’m hoping someone here may be able to point me in the right direction – I’ve signed up specially! I have the below 2 fault codes on a 2011 W204 C220 BlueEfficiency CDI on 165k P0101 - Mass or Volume Air Flow Circuit Range/Performance Problem P2463 - Diesel Particulate Filter Restriction Soot Accumulation About 1.5 years ago I had the engine light come on and into limp mode, I read the fault code and it was the Diesel Particulate Filter Differential Pressure Sensor. I bought a new sensor from the dealer for £60, fitted it, reset the code and the car came out of limp and was fine. This time driving along under heavy load (accelerating on dual carriageway after roundabout) I felt a loss of power which was the car going into limp mode (3k rpm limt). No engine light straight away, but that came on the next time I started the car. Unfortunately I had to drive it for another 350 miles / 15 hours before I could read the code. When I did, I got the P0101 and P2463 codes. I’ve checked around the MAF sensor and no obvious signs of split hoses. The air filter is recent and looking at the ‘live’ OBDC2 data, it shows the MAF as 1.7 lb/min at idle which goes up to around 14 lb/min when driving (in limp mode). Does anyone know what normal figures would be for this engine please? I removed the MAF sensor, it looked clean but I gave it a clean with carb cleaner and then isopropyl alcohol plus contact cleaner on the electrical plug. Retested and live figures were just as before. If I clear the fault codes, they disappear, but both come back as ‘pending’ faults as soon as the engine is started. After a journey or two, both codes become ‘real’ codes and the light comes back on. The codes always show as a pair. The MAF sensor appears to be sending values back to the ECU, but the car stays in limp mode even after a reset. I’m concerned that it’s not regenerating with this fault and limp mode on, so the filter is blocking up – hence the second code. Has anyone experienced something like this? Is there a MAF problem that has caused no regens and hence the filter is blocking, or does a partially blocked DPF cause a MAF issue? For some reason this particular MAF sensor (part no 6510900148) is more expensive than others at £250+ so I’m reluctant to replace it when the existing one could be ok? Any help very gratefully received!