help with whining noise please!

[1998zman]

i have a 1998 z28 with 60,000 miles. i have noticed my car makes a whining sound when idleing that sounds like it could possibly be coming from the fuel pump area but not completely sure because i have listened up under the hood and can hear it a little too. the funny thing is that it never happens (the whining) when i first get into my car like going to work in the mornings but as soon as i stop somewhere and cut the car off and get back in to leave, it makes the noise but only at idle, i can put the car in drive and as soon as i take off the noise stops. it is never a constant whine at idle, the noise starts and lasts for maybe 10 seconds and goes off and when the noise happens it is like a fan kicking on because i can see my volts surge down for a split second but it is not the fan. i just recently put loudmouth pipes on the car and can sort of hear the noise through the exhaust. i just bought a new fuel filter but have not put it on yet. i thought it might be stopped up and the fuel pump is struggeling. and one more thing- after about a week of sitting i crunk the car up and it fired up fine but it was just sruggeling (bogging down) but as soon as i gave it a little gas it was 100% fine. any advise would be greatly appreciated. thanks!

[Redphoenix1998]

It could possibly be the EGR valve or the AIR system. I had that issue on my 98 with the EGR and it was basically the solenoid not opening up. That's the best I can tell you. Are you throwing any sort of codes or anything?

[1998zman]

throwing codes???

[1998zman]

sorry i had to do some research. no codes have been popping up. i guess i need to check around my egr tube.