I just finished changing the fuel pump on my 98 GS400 that has 254K on her. My problem is it starts and idles fine but when I press on the gas pedal I hear a hissing sound coming from the fuel pump area that dosen't stop until I let off the pedal. I searched the other post here andcarefully put everything back together. I put the filter o-ring back into the top of the filter with the other plastic piece.I wonder is it a noisy pump or is there something else going on I drove it around my block and other than the noise it seemed fine. Thanks in advance.