Hi,
This vehicle does have a high-pressure fuel pump (HPFP). There is a supply fuel pump in the fuel tank. It sends fuel to the high-pressure pump which is located on the rear of the left cylinder head. See pic 1 below. If I recall, the pump and high-pressure fuel lines are protected with a shield, so that will need to be removed for inspection.
The HPFP is actuated by the camshaft at the top of the cylinder head and under the valve cover. See if you can tell if that is where the sound is coming from. Now that I think of it, the pump at first sounds like it may be sticking. When you rev the engine, it is likely smacking off the cam lobe. It may have damaged the cam, so we may need to remove the valve cover to inspect the cam.
Try to locate the pump. See if the sound is loudest in that area.
Let me know.
Joe
See pics below. I tried to find as many pics as possible to help locate it. Pic 3 shows the cover. The thermostat housing may also be in the way of the pump.
Images (Click to make bigger)
Thursday, November 9th, 2023 AT 8:57 PM