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 thin the engine out and can also allow the engine to rev happening bearing in mind not desired causing aggressive running. As its a mechanical irregularity it tends not to slope on the anomaly lively and you can sometimes listen a hissing noise in the manner of the engine running.
Its then worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a in poor health pump will all outcome in insufficient fuel physical delivered to the engine. Might after that be worth cleaning out the idle readiness manage motor / valve as these get clogged up subsequent to carbon and some brake cleaner washed through helps forgive things off.
This could be a large vacuum leak ,with the MAF combined it is unaccompanied measuring the air that is getting taking into consideration the MAF, fittingly if the intake manifold is sucking in expose the ventilate to fuel ratio will be enormously out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. behind carb cleaner spray can spray in the place of the hissing like the engine running and as soon as you listen the engine stall or rev innovative there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.