This could be an airleak after the airflow meter, any freshen dragged in here isn t seen by the ECU and appropriately not compensated for and can lean the engine out and can furthermore permit the engine to rev taking place later not desired causing sharp running. As its a mechanical defect it tends not to slant upon the deformity lively and you can sometimes hear a hissing noise subsequently the engine running.
Its furthermore worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a sick pump will every repercussion in insufficient fuel visceral delivered to the engine. Might in addition to be worth cleaning out the idle rapidity control motor / valve as these acquire clogged up subsequently carbon and some brake cleaner washed through helps forgive things off.
This could be a large vacuum leak ,with the MAF similar it is and no-one else measuring the air that is getting in the same way as the MAF, suitably if the intake manifold is sucking in expose the expose to fuel ratio will be no question out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. taking into account carb cleaner spray can vaporizer in the area of the hissing as soon as the engine running and bearing in mind you listen the engine stall or rev higher there is the leak ,could be a bad vacuum hose bad gasket on the manifold.