On my tin top Volvo S40 when I first turn on the ignition a loud tapping noise starts behind the n/s dash and lasts for approx 10 seconds, it then stops and starts again for about 2 secs then stops completely. It also starts tapping if I press the air recycling button. What do you think, sticking relay on a flap or something, suggestions please. Barry

Sounds like a rack and pinion sticking and the pinion grinding on the rack. This is probably connected to a "flap" as you mention for air recirc etc.

Good luck with it as modern cars seem to be built around the HVAC system these days.

[Edited on 13/12/09 by SeaBass]

have you tried the VOC ?

i can cut and paste the problem if you dont want to register .

Working on that air recirc. flap idea. Could it be that due to the damp weather the flap has actually stuck and the mechanism is clicking under the strain of trying to turn it?
This was a common problem on Alfas. The flap had a seal on the edges that when wet sealed the thing shut.
If it is be sure not to just ram it open as you'll break summat in there as I did!

Thanks guys I will try the VOC as suggested. Cheers Barry