99 tahoe fuel pressure

[kingdickvii]

99 tahoe fuel pressure runs about 50psi i understand this is low pressure bleeds off fairly quickly. You turn it on comes up about 58psi then drops to 50psi. Idles about 50psi. Some throttle comes up a little but never over 60psi which i understand the spec is 60-66psi. Thought FPR, replaced no help. So i took the fuel lines out of injector spider and ran a test straight off the pump. Pressure came up to about 10psi when on and immediately dropped to 0psi. Fuel pump check valve? She is running fairly rough at at idle. Thanks for any advice.

Edited November 8, 2018 by kingdickvii

[rjgti]

just checked my 99 5.3 and at idle it is 55 psi at fuel rail.  off it drops to about 43

[carnau]

3 hours ago, kingdickvii said:

99 tahoe fuel pressure runs about 50psi i understand this is low pressure bleeds off fairly quickly. You turn it on comes up about 58psi then drops to 50psi. Idles about 50psi. Some throttle comes up a little but never over 60psi which i understand the spec is 60-66psi. Thought FPR, replaced no help. So i took the fuel lines out of injector spider and ran a test straight off the pump. Pressure came up to about 10psi when on and immediately dropped to 0psi. Fuel pump check valve? She is running fairly rough at at idle. Thanks for any advice.

Got to be the check valve in the fuel pump.