This could be an airleak after the airflow meter, any air dragged in here isn t seen by the ECU and correspondingly not compensated for and can lean the engine out and can moreover allow the engine to rev occurring as soon as not desired causing unfriendly running. As its a mechanical malfunction it tends not to slant on the deformity well-ventilated and you can sometimes hear a hissing noise like the engine running.
Might along with be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can accomplish a quick irregularity find if you unplug the meter and manage the engine without it. if the engine condition is the thesame after that chances are the meter or the membership to it is faulty. Its also worth cleaning the MAF sensor wires, as they can get coated as soon as dirt over grow old which then offsets the reading. Use some entry cleaner or brake cleaner to spray onto the wires to cut off the dirt on no account lie alongside the wires similar to everything as they are completely fragile
This could be a large vacuum leak ,with the MAF partnered it is without help measuring the ventilate that is getting next the MAF, consequently if the intake manifold is sucking in air the ventilate to fuel ratio will be totally out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. once carb cleaner vaporizer spray in the place of the hissing considering the engine management and like you hear the engine stall or rev well ahead there is the leak ,could be a bad vacuum hose bad gasket on the manifold.