woz

yes the maf sensor has been checked

Hello, I have a Forester 2015 diesel that stumbles and sometimes stalls after start-up and until the engine is fully warmed up. The car is currently with a Subaru dealer being diagnosed but they seem to be making little headway. The latest escapade has been to check the timing chains - so far they reckon there is nothing wrong with them. The problem started out with the car hesitating and stumbling usually when the accelerator was applied, after starting and pulling away from home, then pulling away from lights, or after stopping to wait before rounding a corner. It has progressed to the car running so rough as to be essentially undriveable until fully warmed up. DPF has been flash cleaned, intake tract has recently had a carbon clean. The problem pre-dates both of those cleans. I have done a lot of peering at ECU data myself with little success. A fuller history of the problem here. https://www.subaruforester.org/threads/2015-diesel-stalling-with-ecu-freeze-frame-data.809944/ I am located in Australia and posting here because Australia and UK both have the Subie diesels.