my cabriolet mk3.5 with 2.0 8v engine auto developed a hissing noise.
seems to come from the top of the dash area, ie. where the glass meets the dash.
its constant, stable, and not very loud (only heard when windows closed and idling or driving real slow ie parking, car behaves nomrally.
doesn't change no matter what gear it is in, even netural and P
does not change in relation to revs or speed
braking has no effect on the noise nor steering in any direction.
i say its a hiss but its almost like very high frequency hum or a bit like metal scraping metal. i am not sure, sounds a bit like the air-con hiss sometimes u get. but its not the air con i have checked.
any idea what i should check next?
MFA seems to display things nomrally.
Air con is working normal
and again, its not loud by that if i turn the stereo up to nomral listening level, i won't be hearing the hiss.
