Check the hose clips for tightness and inspect the trunking for any cracks or splits and next all the vacuum system, the little bore pipes and fittings for cracks and missing parts. The best quirk to find a leak is to have the engine organization and hot and next spray lighter gas /propane or brake cleaner regarding 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 pull off a fast fault find if you unplug the meter and run the engine without it. if the engine condition is the thesame then chances are the meter or the link to it is faulty. Its as a consequence worth cleaning the MAF sensor wires, as they can acquire coated gone dirt on top of get older which then offsets the reading. Use some gain access to cleaner or brake cleaner to spray can onto the wires to separate the dirt upon no account be adjacent to the wires in the same way as whatever as they are totally fragile
This could be a large vacuum leak ,with the MAF aligned it is isolated measuring the ventilate that is getting afterward the MAF, thus if the intake manifold is sucking in freshen the expose to fuel ratio will be agreed out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. subsequently carb cleaner vaporizer spray in the place of the hissing behind the engine running and bearing in mind you hear the engine stall or rev cutting edge there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.