noise in the dash.. need help

[artandscience]

I've got a '94 Q45 (210k miles) and I've recently got a noise in the dash aboutin the area of the stereo/clock.. It sounds a bit like something flapping. The A/C seems to work fine, as does the heat and changing the airflow selection (feet, head, mixed) doesn't seem to affect it. No apparent leaks.

I'm wondering if air in the A/C system or in the cooling/heating system could caus this - is it cavitation perhaps? My next thought is to check the fluid levels in the radiator and in the A/C system.

Any suggestions welcome. With the heating/cooling completely off, I still get the noise.

thanks,Stefan

[qship96]

Low coolant causing air pockets and the gurgling. Fill radiator and overflow bottle and keep eye on it for a few days as overflow tank level will drop as air pockets burp themselves and are replaced by by coolant