fuel pump relays

[chris989]

Hello,
1989 v2500 5.7.

Can someone walk me though trouble shooting my fuel relays. I have wire diagrams but just can not figure out an easy way to test.

My truck runs fine but every first start of the day it has to crank. I believe the "start relay" is not working and I am not getting fuel pressure until I have oil pressure.

What i have read is there is a second relay that primes for a few seconds but stops and then the oil pressure/fuel takes over. I think the prime relay is not working. My pump is so quiet i can not hear it run.

If someone can simplify this circuit at the firewall it would be a great help.


Chris