Check the hose clips for tightness and inspect the trunking for any cracks or splits and then all the vacuum system, the small bore pipes and fittings for cracks and missing parts. The best way to locate a leak is to have the engine management and warm and subsequently vaporizer lighter gas /propane or brake cleaner concerning each joint in turn. If the engine rev s in the works you ve found your leak.
Might as well as be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can accomplish a fast fault locate if you unplug the meter and control the engine without it. if the engine condition is the similar later chances are the meter or the connection to it is faulty. Its with worth cleaning the MAF sensor wires, as they can acquire coated next dirt higher than become old which then offsets the reading. Use some gain access to cleaner or brake cleaner to spray can onto the wires to surgically remove the dirt upon no account lie alongside the wires in imitation of anything as they are completely fragile
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you stirring to date on all maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms taking place and is warmed up? oftentimes in engine statute many factors may cause the similar symptom(s)