Dueling fuel pumps causing a pulse?

[billschroeder5842]

I noticed a "faint pulsing" this morning when I firsted headed out.

I started my 91 and without warm up drove easy for a few miles. I noticed upon light acceleration I felt a faint "pulse" every 1/2 second or so. On steady cruise the pulse was gone so I'm suspecting fuel pressure.

The car has 82k, new FIC injectors, headers and a tune (Thanks Steve Schroeder!) in February this year. The fuel pumps are original.

After my stop, and with the car fully warmed, I drove home with no pulsing or performance degradation. I popped a fuel pressure gauge on the engine and it showed 40 at idle. I taped the gauge to my windshield and took it out for a quick ride. I got on it and showed (after a quick blip down after punch)40 at cruise and 48 with WOT.

So, I know that upon cold start both fuel pumps run til the engine get to 172-ish or so when the secondary shuts off and the car operates on main. Could that pulsing I felt be "Dueling fuel pumps?"

I'm not super worried just more curious than anything. Thanks!