Fuel Pump Whine

[RPGR90s]

I recently took a long trip (about 1500 miles) where my 2000 convertible, 57k, ran extremely well.

Upon returning home, I filled up about 200 miles away (Marathon gasoline in Greenville, OH) and a few miles later, the Check Engine light came on. I had no drivability issues but checked the codes when I got home (P0172, and P0175).


During the week long trip I noticed on occasion a loud whining sound coming from the fuel tank area while driving. Sometimes I would start the car and it would be there, the next time I couldn't hear it.



Before the trip I swapped out the fuel filter for the stock ACDelcoGF822 and drove it for about a week with no issues.



I cleaned the MAF sensor and decided to check the fuel rail pressure just in case it was a fuel pump failing.


With the ignition on, fuel pressure is 28psi and slowly falls.


When I start the engine, pressure goes to 60psi, but a few seconds later, the fuel pump started making noise and I saw the pressure rise to over 120psi.



I killed the engine, thinking that pressure is waaaay too high and might damage something.



I would appreciate any direction you can give.



Thanks,

RPG

[grumpyvette]

P0172 - Fuel Trim System Rich Bank 1
P0174 - Fuel Trim System Lean Bank 2
P0175 - Fuel Trim System Rich Bank 2

sounds like the oxygen sensors , indicate excess fuel, maybe some excess moisture in the fuel, caused issues,
falling fuel pressure is likely related to a stuck open fuel injector(s) or defective fuel pressure regulator or the fuel pump is going bad
all the symtoms could be related to one or more injectors partially or intermittently stuck open.
why not throw 8 oz of marvel mystery oil and a can of injector cleaner in your next fuel fill and see if it helps before you get concerned