no fuel spray on start

i got a 1993 cheyenne 4x4. the truck will not start without priming. i have to unplug iac prime and let idle for 10-15 minutes. after that i'am good to go. i can shut truck of and restart if i do not leave her to long. i changed fuel pump a couple of times. fuel comes to trottle body but will not spray without priming on cold start. i never checked fuel pressure. any help appreciated.
thanks

Check the fuel pressure off and at idle. Should hold pressure.

thanks for the reply taillight. so even what seems to be good gas flow at the trottle body. the pressure may not be there. correct? i do not see a place to check for pressure on top. i think its down under in a hard spot to get at. can someone let me know. thanks.

i forgot to mention that i bought a cheap codereader and got the following code errors 15,22,54

What engine? You may have to break into the fuel line.

v8 7.4

My book says there is a fuel pressure connector in the line. I don't know where it is but there is one

I found one on a 7.4 in an 98. The valve is on the front of the fuel rail.