2000 Tacoma 2.4l trouble starting after sitting overnight

Have replaced injectors and fuel pump.Seems to run better and will start after just being ran or even 30 minutes later but when it sits overnight it is hard to get started. Does the fuel system have a check valve that maybe not working? Or is there a check valve inside the fuel pump and maybe I got a dud when I got the new fuel pump? Any help would be appreciated.

 

There is a check valve in the fuel pump that is supposed to keep fuel from bleeding back to the tank.

You really need a fuel pressure gauge connected to check if fuel pressure is holding with the engine off.

 

Describe "hard to start". Does it crank strong? How long does it take to start? Does it stumble or cough when starting? That sort of thing...