Strange WUR behavior

[Outwesty]

I've never seen a WUR fail this way. I'm curious if anyone else has.

Cold engine. Fuel Pressure tester valve open (control) . Run fuel pump and I get 12PSI (its 32F today). If I close the valve I get 75 PSI primary. When I switch back to control pressure at this time I get a steady 65PSI. If I release system pressure and do the test over. Same thing. pump running at 12 psi. switch to primary and I get 75, switch back to control and 65 every single time. Inlet screen is not plugged.

[Bitsyncmaster]

I've never tested control pressure without the engine idling. I think your 12 PSI is good and so is your 75 PSI.

[Outwesty]

I've never tested control pressure without the engine idling. I think your 12 PSI is good and so is your 75 PSI.

But the 12 control is 65 once you switch to primary and then back to control. Doesn't make sense.

[Bitsyncmaster]

But the 12 control is 65 once you switch to primary and then back to control. Doesn't make sense.

I bet if you press the air plate the 65 would drop back to 12 again. So with the engine running you would not see that 65 PSI.