I was driving back home from work today when my windscreen started getting misty so I switched the electric demister on. In the past it has caused the car to sound slightly more laboured than normal but today I'm getting vibrations and it's noticeably louder! The noise comes from behind the front left wheel and slightly up (about level with the uppermost curve of the wheel arch) inside the engine bay. I hear the metallic vibration noise more often than not but more so when I turn the demister on. I know the fuel pump is now placed in the engine bay of the mk7.5 fiesta ecoboost but I've checked that and whilst it's noisier than most cars I've driven, the noise is not coming from that. Any ideas?