occasionally i hear a loud screeching (sounds like metal on metal) when i start the car after a few days of non use.

sometimes there is no screeching until i turn on the a/c.

goes back to normal after 30 seconds or so.

what could be the reason for this?

2000 cefiro, about 102000 kms, had service done at around 100k.

any place where i can get this checked besides gallery on libis (heard not so pleasant things and had strange experience there)

tia.