This could be an airleak after the airflow meter, any air dragged in here isn t seen by the ECU and thus not compensated for and can thin the engine out and can plus permit the engine to rev up later not desired causing harsh running. As its a mechanical fault it tends not to slope upon the malfunction vivacious and you can sometimes hear a hissing noise when the engine running.
Thanks for your response. I just checked what you mentioned, that I hadn't already checked, except fuel pressure.Let me say you a tiny more just about the suffering history. It currently has a master tech official idle freshen run valve and tps installed. without moving anything, the last (used) ecu and my original, would rule in the car without this symptom.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you taking place to date upon every maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms occurring and is warmed up? oftentimes in engine deed many factors may cause the thesame symptom(s)