I need the help of some of the experts in our community .This will be a multi point question so please be patient with me.
First off the other day I go for a spin and hear a high pitched whine from what seems like the underside of the car. Since I wasn’t dressed for the task of investigating I stopped at the dealer which is pretty much at the end of my street. The head tech said it sounded like a fuel pump and we pulled the access cover off and it did appear to get slightly louder. OK it must be a failing pump; but the car seems to perform no differently than before. I shut the car off and we BS about a beautiful ’78 they had in there, just like my old car and when I get ready to leave there is no noise at all from the pump and it seems to run fine. Then down the road about 10 minutes of stop and go traffic the noise just re-appears. (WTF) It is so loud people on the sidewalk probably thought I had a 2000 hp Weldon pump in the car!
I am puzzled because in my experiences with other cars the noise never stops until the pump quits and the vehicle performance suffers in the meantime.
The car is 2001 EVO stg4 and has a stock fuel pump.
When I had time later I popped the access open and pulled the fuel pump out (yes had to make a little special tool for this) and inspected the lines which seem to be OK.
My questions are these:

Is this typical to the Porsche pumps when they fail? (I know there are those of you that have had failures)

Is there any other pump up front or in the front area that may be failing? (Not sure if Porsches use a coolant transfer pump from the rad back to the engine water pump)

What are the flow ratings of the stock pump? (I plan to get it bench flowed and need a standard to go by)

What is an upgraded pump(s) to install? (if any and if not I will be building some sort of system!) I would rather take a step forward towards a better system because as we all know the mod disease can strike at any time and I will want more power!

What do some of the high HP guys use in the GT700-950 ++ cars for fuel delivery? I would rather put a higher flow pump in than the stocker if it is in fact bad.

Also what is stock fuel pressure?


Thanks to all in advance for any input.

 

Before we go down the fuel pump questions...are we sure it is the fuel pump? The whine you describe...is it only noticeable at low RPMs? Does it stop with clutch engaged? If so go here:
LINK

 

im gona double check tonight after work but if i remember it was clutch in or out in gear or neutral.

 

Specs for stock fp

Engine not running: 3.8 +/- 0.2 barEngine at idle: 3.3 +/- 0.2 bar

 

I took the pump to our guys that flow check all the fuel issues so i'm gonna get numbers off this thing no matter what. I usually get a complete flow chart vs voltage/pressures etc. so at some point this may be helpful.