1998 Chevy tahoe Hard to start when cold

My 1998 chevy tahoe with 5.7 Liter, 4X4 Automatic is hard to start when the motor is cold, runs good & starts ok when it is warmed up. Acts like it may be flooded. I've replaced the fuel pressure regulator & fuel filter. The fuel pump has been replaced about 16 months ago (twice). There isn't any fuel pressure in the lines after it sits for a short time, where is the fuel pressure draining to? Thought it might be the check vavle in the fuel pump, or the seals in the fuel injection module. I have a 5.7 liter Vortec and takes two maybe three cranks to start. After warm starts every time. I have recently replace fuel pressure regulator and did not help. Any advise, thanks