This could be an airleak after the airflow meter, any air dragged in here isn t seen by the ECU and for that reason not compensated for and can thin the engine out and can moreover permit the engine to rev happening taking into consideration not desired causing scratchy running. As its a mechanical fault it tends not to slant on the malfunction lively and you can sometimes hear a hissing noise taking into consideration the engine running.
Might after that be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can realize a quick anomaly find if you unplug the meter and control the engine without it. if the engine condition is the similar later chances are the meter or the connection to it is faulty. Its furthermore worth cleaning the MAF sensor wires, as they can acquire coated considering dirt higher than get older which after that offsets the reading. Use some right of entry cleaner or brake cleaner to vaporizer onto the wires to remove the dirt on no account be next to the wires considering all as they are no question fragile
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you taking place to date on every maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms going on and is warmed up? oftentimes in engine exploit many factors may cause the thesame symptom(s)