scan tool still shows rpms when it loses power

Runs fine til warm, then loses power and dies. Will restart - no codes.
Distributor & crankshaft position sensor replaced.
Any ideas? Appreciate any help.

There were no codes and most likely the cause, but did not fix

After replacing fuel pump and mass air - call still falls flat under acceleration. No engine light on. Idles good at times, stumbles & dies at times.
Removed O2 sensor, no difference. Any suggestions?