00 Honda Civic Makes squeaky noises when stepping on the gas.?

My 2000 Honda civic seems to be making a weird hissing/gargling sound every time I give it gas. It tends to make a squeaky hissing sound when I start it up in the morning and as I stop and go on the road it makes a gargling sound when I step on the gas. Note it doesn't make any noise if I floor it or apply alot of pressure to the pedal or if i am driving over about 45 miles per hr. Any suggestions??