This could be an airleak after the airflow meter, any expose dragged in here isn t seen by the ECU and hence not compensated for and can thin the engine out and can moreover allow the engine to rev occurring in the same way as not desired causing rude running. As its a mechanical malfunction it tends not to slant on the malfunction spacious and you can sometimes hear a hissing noise in imitation of the engine running.
Its also worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a poorly pump will every repercussion in insufficient fuel innate delivered to the engine. Might furthermore be worth cleaning out the idle rapidity govern motor / valve as these acquire clogged in the works subsequent to carbon and some brake cleaner washed through helps release things off.
This could be a large vacuum leak ,with the MAF combined it is by yourself measuring the ventilate that is getting once the MAF, so if the intake manifold is sucking in freshen the expose 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. behind carb cleaner spray can spray can in the place of the hissing in imitation of the engine government and gone you hear the engine stall or rev far along there is the leak ,could be a bad vacuum hose bad gasket on the manifold.