vacuum leak??

hello
I have this problem with my 91 chevy truck were when i accelerate i hear a buzzing noise and it stops if i let my foot of the gas.. does anyone know wat this is??
thx for anything

If the truck is running fine, here is a thought. Check your gasket under the air cleaner to TBI.

my truck runs fine untill the service light comes on, then my mileage really sucks. I just recently installed a throttle body spacer and used the gaskets that came with it, should i go to napa and get new gaskets you think??

what does the code read?

its code number 32

here's what it say's for code 32:
32 EGR open command did not change MAP sensor signal. Normal EGR flow should cause slight decrease in manifold vacuum which would change MAP sensor signal.
could mean that the buzzing sound is a vacuum leak. check vac lines and egr valve to make sure it isn't leaking anywhere's.

ok thanx

i just replaced my EGR and im heading out on the road tomorow so ill see if it helped, thanx for all the help