Now you might think that spraying lighter gas nearly a warm engine isnt wise, however the flash /ignition narrowing of gas is just about 400C for that reason you compulsion a naked ember or spark to set it off and Ive used this method for many years without incident. exploit your pretentiousness through each possible joint one at a period and you should find it. I use a slightly flattened piece of brake pipe and some rubber hose from the can of lighter gas to provide a spraying wand and allow a take in hand blast of gas into each area, especially those hard to reach following large implements.
Might in addition to be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can reach a quick anomaly locate if you unplug the meter and rule the engine without it. if the engine condition is the similar after that chances are the meter or the link to it is faulty. Its moreover worth cleaning the MAF sensor wires, as they can acquire coated in the manner of dirt beyond become old which later offsets the reading. Use some edit cleaner or brake cleaner to spray can onto the wires to remove the dirt upon no account touch the wires bearing in mind all as they are unconditionally fragile
This could be a large vacuum leak ,with the MAF associated it is deserted measuring the air that is getting following the MAF, as a result if the intake manifold is sucking in freshen the ventilate 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. later than carb cleaner vaporizer spray in the area of the hissing bearing in mind the engine running and like you hear the engine stall or rev innovative there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.