This could be an airleak after the airflow meter, any ventilate dragged in here isn t seen by the ECU and in view of that not compensated for and can thin the engine out and can also allow the engine to rev taking place later than not desired causing coarse running. As its a mechanical irregularity it tends not to slope on the irregularity blithe and you can sometimes listen a hissing noise similar to 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 in poor health pump will every outcome in insufficient fuel creature delivered to the engine. Might as well as be worth cleaning out the idle promptness control motor / valve as these acquire clogged taking place gone carbon and some brake cleaner washed through helps release things off.
This could be a large vacuum leak ,with the MAF connected it is single-handedly measuring the let breathe that is getting subsequently the MAF, in view of that if the intake manifold is sucking in air the let breathe 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. subsequent to carb cleaner vaporizer vaporizer in the area of the hissing with the engine paperwork and behind you hear the engine stall or rev innovative there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.