Check the hose clips for tightness and inspect the trunking for any cracks or splits and along with every the vacuum system, the little bore pipes and fittings for cracks and missing parts. The best pretension to find a leak is to have the engine organization and warm and subsequently vaporizer lighter gas /propane or brake cleaner a propos each joint in turn. If the engine rev s taking place you ve found your leak.
Might along with be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can realize a quick oddity find if you unplug the meter and rule the engine without it. if the engine condition is the similar then chances are the meter or the membership to it is faulty. Its next worth cleaning the MAF sensor wires, as they can get coated bearing in mind dirt higher than mature which then offsets the reading. Use some door cleaner or brake cleaner to vaporizer onto the wires to surgically remove the dirt upon no account be adjacent to the wires past everything as they are completely fragile
This could be a large vacuum leak ,with the MAF united it is only measuring the freshen that is getting later than the MAF, for that reason if the intake manifold is sucking in ventilate the ventilate to fuel ratio will be enormously 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 vaporizer vaporizer in the place of the hissing taking into consideration the engine management and later you listen the engine stall or rev innovative there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.