I'm pretty sure it's all of the problem. That happened to mine. I got ripped off to get it fixed. The shop charged me almost 200 to diagnose/fix that and charge my a/c. U can get it off of ebay for around $3. For example....
http://cgi.ebay.com/ebaymotors/mk3-s...QQcmdZViewItem
and its definitely not $6 to ship it. it weighs almost nothing.