Glad you got it sorted. It really could only have been that problem, talk of throttle position sensors made me whince. Never mind, as long as somebody learned something that is all that matters.
I can understand them looking directly at the flow meter if it was just cutting or fluffing at 4000 rpm. But all the symptoms mentioned, On low fuel, Around right hand bends, Up hills, Ok when stationary. Points directly at fuel starvation caused by fuel slosh and a bad pickup. There could have been no other cause. Driving up hill, around a right hand bend, on low fuel cannot effect the airflow meter.
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