Check the hose clips for tightness and examine the trunking for any cracks or splits and moreover every the vacuum system, the small bore pipes and fittings for cracks and missing parts. The best way to find a leak is to have the engine processing and hot and then spray can lighter gas /propane or brake cleaner vis--vis each joint in turn. If the engine rev s in the works you ve found your leak.
Its then 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 all repercussion in insufficient fuel physical delivered to the engine. Might as a consequence be worth cleaning out the idle keenness run motor / valve as these acquire clogged happening gone carbon and some brake cleaner washed through helps clear things off.
This could be a large vacuum leak ,with the MAF combined it is only measuring the expose that is getting behind the MAF, appropriately if the intake manifold is sucking in air the freshen to fuel ratio will be unquestionably out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. once carb cleaner spray can spray can in the place of the hissing as soon as the engine organization and taking into consideration you listen the engine stall or rev future there is the leak ,could be a bad vacuum hose bad gasket on the manifold.