i have a 98 blazer v-6 vortec motor and i have a whinning noise coming from fuel tank area not sure what it is or what to check first????

i also have a engine light on with the code p0440 code checked gas cap and fill hose and it all looks good the intake gasket was busted and leaking so i replaced that and after about 30 min of driving the light went off and then after prolly 20 miles or so over 2 days the light came back on..... same code.....what do i need to do i kno enough about car to fix myself as i did the intake job in my backyard PLEASE HELP NEED TO GET INSPECTED

 

chances are its the fuel pump making the noise,which is normal. you shouldnt beable to hear it really loud,but alot of them do make a noise. Doesnt mean its bad,but some are loud.

 

i would get a new gas cap...its probably your problem. or you arent making it click enough when you are putting it on. a buddy of mine had to click his 3 times or it would throw on a CEL. if you clicked it 2 or 4, it would throw the light on.
as far as your tank making noise, you should start saving for a fuel pump. it might be on its way out. i have 2 98's and one has a new fuel pump in it. you cant even hear it. my other one is super loud and i am dreading having to do it. but o-well.

 

My first Delco pump I put in was quiet. Couldn't hear it at all. I had some fuel system problems, thought it was the pump (but I don't think it was... kept the first pump as a spare), so I bought another Delco and put in. That second pump is much louder than the first. You can hear it in or outside the truck.

If it's always made a noise, I wouldn't worry too much about it. But if it has always been quiet, and suddenly starts making noise, probably best to start saving up for a new pump.

 

You don't need much of a hole in the fuel filler neck to get a code.

 

My fuel pump is loud as crap! But it seams to be working just fine so I'm not going to fix what ain't broken