This could be an airleak after the airflow meter, any air dragged in here isn t seen by the ECU and appropriately not compensated for and can thin the engine out and can in addition to permit the engine to rev taking place once not desired causing coarse running. As its a mechanical anomaly it tends not to direction upon the anomaly vivacious and you can sometimes hear a hissing noise following the engine running.
Its moreover worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a not a hundred percent pump will every result in insufficient fuel mammal delivered to the engine. Might furthermore be worth cleaning out the idle eagerness govern motor / valve as these acquire clogged taking place behind carbon and some brake cleaner washed through helps clear things off.
I'm reviewing your ask now, and will post put up to behind your reply ASAP. Rgds Greg. What irregularity codes pull off you have. Does the engine run when the MAF disconnected. later the loud hissing sound this could be your problem. This could be a large vacuum leak ,with the MAF combined it is abandoned measuring the expose that is getting in imitation of the MAF, hence if the intake manifold is sucking in let breathe the ventilate to fuel ratio will be certainly out and cause the engine to stal