There is a hissing noise when I press the gas pedal. It gets quieter when I don?t, louder when I press harder. It also gets louder the longer I drive. Sounds like a soft hiss, and then turns out into something like scratching of sand on glass.
Anyone has an idea what it could be? It?s not there when the engine is cold, so the service guys didn?t hear it (they didn?t test-drive it long enough).
I?d really appreciate the help.
Last post for today. Merry Christmas everyone and goodnight.