311k and have never done any AC work, but she is not working correctly.....sometime it is cold, most of the time not.....had a HVAC on the job try to add some R134 and said it only had 4lbs.....he said he could here clutch clicking and trying to engage but wouldn't......ac clutch replacement?....take it to shop for diagnosis?....never done any AC work, definately novice in this area. Thanks!