Frequently but intermittently while driving I take my foot off the gas pedal to slow down before braking. When I take my foot of the pedal, it creates a noise as low as a two-tone hum sound to a rubber bicycle horn sound to a chainsaw sound. My husband wonders whether there is something going on with the fuel pump. Help.
“a rubber bicycle horn sound to a chainsaw sound” I am having a little trouble imagining the sound. Can you try a little more description?
Type/age of vehicle?
I cannot imagine why a fuel pump would make noise when you take your foot off the gas. The most common noise when you take your foot off the gas is a heat shield vibration, which is usually a high-pitched metalic chatter. The second most common noise when you take your foot off the gas is a vacuum leak whistle.
I don’t think it’s the fuel pump. Does the ventilation system change in any way when this happens?
I’m suspecting something controlled by vacuum is making the sound, and on many cars the ventilation system has vacuum-controlled devices which can sometimes make the sort of noise you describe when they move.