Chevrolet Repair: 1994 Chevy 1500 v-6 4.3 throttle body inj, pressure control valve, vacuum leak

Question
When checking fuel pump pressure it drops down to 9 lbs at Idle. It does go to 13-15 when reved up. Should'nt it be 12- 15 lbs at all times?
Thanks
Dennis

Answer
In a word...yes.
Fuel pressure control valve comes to mind, but a vacuum leak also comes to mind, since it is vacuum dependant.
Vacuum would seem to be the only thing changed by revving the engine, unless you have some electric connector problems, and speeding up the alternator gets more voltage to the in tank fuel pump....but I doubt that.
I would check the vacuum at the pressure regulator.
Van