engine losing power

After it loses power how long does it take to come back? Do you have to shut off the engine or just let it idle a bit?

The description suggests it has a weak fuel pump that cannot keep up with the engine demands when under load. It could also be a bad regulator mimicking the same issue due to the lower vacuum at high rpm.

A fuel pressure and flow test would be a good place to start.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

no have to shut the car down once this happens. I shut the car down and after the car sits or cool off it will run again for fifty to eighty miles and starts the problem again.

Okay as a strange test. Run it until it shuts off, then remove the fuel cap. Listen to see if you hear a hiss. It is possible the tank vent is plugged, but it sounds fuel related.

the car does not completely shut off it will idle okay. and no check engine light comes on. I checked the battery and the battery is bad. good enough to start, but when the car gets hot, not overheated could it be not enough spark. had a new alternator and belt put on two weeks ago. or could it be the gas cap?

Bad battery should not make it lose power if the alternator is working. I would check fuel pressure and flow. Plus check the cap.

Okay thanks, I will check that tomorrow. Vince

Your description of shutting it off to cool down sounds like the pump is failing. It cannot keep up with the flow and the mix starts to get lean which generates enough heat that it actually starts to vapor lock because the flow is not enough to keep colder fuel running through the lines. I might also swap the fuel filter as that could reduce the flow as well.

Thanks I will change the filter than the pump. Vince