hi i have a 1995 volvo penta 5.8Fi in a four winns. when i hit 2700 rpm it runs fine. when it goes to 2800rpm the engine starts bucking like it is not getting enough fuel or air. when i bring the rpm below 2800 it runs fine again. i changed out the water separator and cleaned the air filter also put high premium fuel in, fuel injector cleaner in and ran it for about 10 hours but still no difference. any thoughts?
