1985 Pontiac Trans 305 injection

1985-pontiac-trans-am
Every time I make a right hand turn my engine shuts down and acts like it’s out of fuel. It won’t start again until I keep pumping the pedal continuously. It can take up to ten minutes to get going but as soon as I turn right it shuts down again. please help. I feel like I have been to every mechanic in Melbourne and all they do is fill the tank up and say they can’t find it, but once the tanks on half way it starts happening. I keep telling them but they don’t listen. thanks for your time.