Sometimes I have to use starter fluid to start my 5.7 engine in my 95 Chevy Tahoe but once I do it’s fine for a while then I have to use the fluid again to start it.this just started happening a few days ago.
The next time you go to start the engine, instead of using starter fluid, turn the ignition switch on so the dash lights come on for two seconds, and then turn the ignition switch off.
Repeat this a half dozen times and then try starting the engine.
If the engine starts right up, it points to a problem with the anti drain-back valve on the fuel pump.
Suggest to read the last part of the link below about the fuel pressure hold test.