While cleaning out the air intake system this weekend, I decided to test the operation of the air box thermostat per the Haynes procedure (i.e., stick it in the freezer for 5 minutes and see if the flap has closed off the cold air flow). Looks like it only closes about 2/3 of the way. Once it heated back up (about 90 degrees) it was only partially closed on the other side. My question is just whether the thing is shot, or is the description of its function incorrect. Is it really ever supposed to fully close in either direction? Is it worth replacing (i.e., does it actually help or hurt engine function)? (about $25 from alloemvolvoparts.com) My 95 GLT (N/A) has about 130K miles, and I haven't noticed any degradation in performance. Thanks in advance.