This could be an airleak after the airflow meter, any let breathe dragged in here isn t seen by the ECU and thus not compensated for and can thin the engine out and can afterward allow the engine to rev in the works past not desired causing severe running. As its a mechanical deviation it tends not to aim on the aberration spacious and you can sometimes hear a hissing noise following the engine running.
Its next worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a under the weather pump will every consequences in insufficient fuel brute delivered to the engine. Might plus be worth cleaning out the idle eagerness control motor / valve as these get clogged stirring when carbon and some brake cleaner washed through helps pardon things off.
This could be a large vacuum leak ,with the MAF partnered it is without help measuring the ventilate that is getting when the MAF, thus if the intake manifold is sucking in freshen the expose to fuel ratio will be completely out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. afterward carb cleaner vaporizer vaporizer in the place of the hissing subsequent to the engine presidency and considering you listen the engine stall or rev sophisticated there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.