can you be a bit more specific??? Buzzing sound from underneath is kinda wide open.

 

My truck has been making a funny noise lately. when i start it up it is making a buzzing sound that comes from under it. It usually quits withing 20 secods or so. I'm going to try to record it tomorrow to see if that helps getting the problem diagnosed. Anyone else have this issue? Mines an 06 with 25000 miles.

Electric fuel pump? It makes noise as it pressurize the system. Could that be what your hearing?

 

yeah, my titan is making all kinds of noises now... not too sure what the heck is wrong with it!!

 

Electric fuel pump? It makes noise as it pressurize the system. Could that be what your hearing?

Thats the first thing that came to my mind too. have the dealer check it out and pressure test

 

To be a little more specific. It sounds more like a vacuum line/air type whistle/buzzing. And it does it in park and usually will stop as soon as I put it in gear. I'm gonna bring my camera today so I can record it when it does it next.

http://s35.photobucket.com/albums/d200/msinwelski/?action=view&current=MOV01153.flv

You can't hear it real well over this video but you can hear when it quits when I put it in gear.

 

Check the fluid levels in power steering and transmission. It may be a longshot but it is very easy to do. Some types of pumps will make a growl when sucking air.

 

Could be electric fuel pump.That always buzzes when I start it up.That is probably wat it is.

 

my buzzing-like sound was a loose heat shield.

 

My dealer cut-off all of exhaust heat shields when I brought it in about the noise. Some fix eh?