I just changed had to change the fuel pump in my 99' Suburban. After the install I noticed a low pitch humming noise coming from somewhere around the engine. You can't hear it real well when you pop the hood because of all the other engine noise but you can hear a lot better from inside the cab. But while driving as soon as you give any throttle at all it goes away and as soon as you let off it comes back. At first I thought it was just my blower for my heater but it was turned off. So now I am not sure where to look. I did crawl back under neath by the fuel tank to see if maybe it was the fuel pump but it is quiet back there. Any Ideas?

 

Hi sorry I'm not writing with what solution is to your problem but rather with a request. I'm having a heck of a time putting the new pump back into the tank. The o ring that goes on the pump will just not allow the pump to drop back in. Did I have that problem too? If so how were u able to finally drop the new pump in

 

Be sure you grease the o-ring with some vaseline or something similar and twist a little as you put it in there. If dry it's going to be almost impossible.