I have a 5.7L vortex in 1997 K2500. I thought I wasn't getting enough fuel to the Intake so I changed the Fuel filter first. Then when I tested the Shrader like valve in the supply line it was not always pressureized. So I changed the in the tank fuel pump. Now it runs GREAT ... for 20 to 3 seconds. I was told there is a fuel pressure regulator but I can not find it anywhere on the fuel line. could this being bad have damaged my fuel pump in the first place? and where the heck is it? I can't find it anywhere.