Fuel pump or filter

99 silverado auto 5.3. driving homme, the truck lost power, like running out of gas.

it would still idle. push on the gas , nothing would happen for a few seconds, then rpm would come up and hold.

That’s a hard choice: a $20 dollar part or a $200 part! Since the fuel filter is probably original, and 70,000 miles past due, I would go with a new fuel filter; then, test the fuel pressure.