- highwaywarrior wrote:
- hey guys, i was driving to the bank and got out of my 98 riviera and left it running. i heard a noise ive never really noticed before.. slight whirring under the back wheels ( not air ride). i know i hear the fuel pump when i intially starts but is it supposed to have a noticeable whirring at idle? should i be looking for a fuel pump?
You can have the fuel pump tested by a mechanic using a Tech II to command it on.
You can inspect the connections for corrosion (which affects operation by reducing current) by removing the panel in the trunk (under the carpet, can't miss it). If this is the problem correcting it won't silence the pump but will allow it to operate the best it can.
You can check the fuel pressure at the Schraeder valve on the fuel rail.
You can replace a noisy fuel pump - every one sounds a bit different in operation though.
The fuel pump makes a good bit of noise, but is not readily noticeable when car is in normal operation. You can reckon the noise. After the car has been parked for at least, say ,an hour or so just turn the key to the ON position and listen. You will hear the fuel pump whirr. During the startup sequence, after the PCM finishes its basic systems checks, it then activates the fuel pump to prime the engine. The air ride inflates the suspension after a minute or so, I don't remember how long.