Check the hose clips for tightness and inspect the trunking for any cracks or splits and moreover all the vacuum system, the little bore pipes and fittings for cracks and missing parts. The best way to locate a leak is to have the engine dealing out and hot and subsequently vaporizer lighter gas /propane or brake cleaner going on for each joint in turn. If the engine rev s happening you ve found your leak.
Might with be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can complete a quick irregularity locate if you unplug the meter and rule the engine without it. if the engine condition is the thesame next chances are the meter or the association to it is faulty. Its afterward worth cleaning the MAF sensor wires, as they can get coated like dirt higher than era which after that offsets the reading. Use some log on cleaner or brake cleaner to vaporizer onto the wires to sever the dirt upon no account be next to the wires considering everything as they are certainly fragile
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you going on 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 going on and is warmed up? oftentimes in engine put-on many factors may cause the similar symptom(s)