This could be an airleak after the airflow meter, any freshen dragged in here isn t seen by the ECU and suitably not compensated for and can lean the engine out and can furthermore permit the engine to rev taking place following not desired causing rasping running. As its a mechanical malfunction it tends not to position on the deformity lively and you can sometimes hear a hissing noise considering the engine running.
Might afterward be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can pull off a quick malformation find if you unplug the meter and rule the engine without it. if the engine condition is the similar then chances are the meter or the association to it is faulty. Its along with worth cleaning the MAF sensor wires, as they can acquire coated with dirt beyond mature which then offsets the reading. Use some way in cleaner or brake cleaner to spray onto the wires to surgically remove the dirt upon no account touch the wires subsequent to whatever as they are entirely fragile
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you going on 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 happening and is warmed up? oftentimes in engine appear in many factors may cause the thesame symptom(s)