Sonoma running rough

Hey everyone, I have a automatic 99 Sonoma 4.3 Vortec. One day I was driving about 50 mph and I just felt power loss. Almost the same feeling as when your running out of gas, or bad gas . I could still drive it but when you get to about 20 mph it starts hesitating as if it wants to die. I've had people tell me it could be the fuel pump/filter and also maybe the catalytic converter. I would appreciate any suggestions I can get, Thank You.

Have you checked fuel pressure and leakdown? Have you replaced the fuel filter?