Latest problem: Fuel pump humming?

[johnsonace]

My '98 GS w/ 168k has started humming. The sound comes from under the car towards the rear axle.
It doesn't start until the car is fully warmed up and driven several miles.
My initial thought was an exhaust leak, & I even imagined I saw evidence along the seam in the muffler.
The mechanic at the muffler shop says it's the fuel pump. He thinks its pretty common on lots of GM vehicles but won't offer a prognosis.
I plan to change the filter this weekend in the unlikely event that it may be causing excess back pressure.
Anybody here experienced this sound?
Does it preceed a FP failure or is it just a nusiance noise?
Anybody got a link to FP replacement procedure?

[BNaylor]

Probably just a nuisance for now but you never know for sure. See link below for fuel pump replacement.

Click here

[stripe]

Originally Posted by johnsonace

My '98 GS w/ 168k has started humming. The sound comes from under the car towards the rear axle.
It doesn't start until the car is fully warmed up and driven several miles.
My initial thought was an exhaust leak, & I even imagined I saw evidence along the seam in the muffler.
The mechanic at the muffler shop says it's the fuel pump. He thinks its pretty common on lots of GM vehicles but won't offer a prognosis.
I plan to change the filter this weekend in the unlikely event that it may be causing excess back pressure.
Anybody here experienced this sound?
Does it preceed a FP failure or is it just a nusiance noise?
Anybody got a link to FP replacement procedure?

You should hear the pump when you turn the key to on.
Turn off the radio and close all windows and doors.
Turn the key. pump will be heard.
If you have good pressure don't worry.
Your car will just stop if the pump quits.


Cheers
Stripe