Good time to point out safety with A/C. I had a customer come in yesterday with an expansion valve in his hand. He said he was doing fine removing it until the freon began spewing out under pressure and soaked him.
I want to suggest that anyone doing work on A/C systems who doesn't have some training and a set of proper gauges is looking for an injury. It's just a little safer than changing a fan clutch on a running motor - just a little safer - since most of the diagnostics have to be performed on a running motor. A gauge set tells you what's up, not a guess at what may or may not be a symptom, and then blaming a part you didn't test.
My customers symptom was that the low side pressure was 108 pounds - not running. The compressor is also the suction motor for the low side, and if it's not running, no low side pressure is very accurate. So he basically dumped 4 pounds of R134 at $7.99 a can blaming the wrong part - a part not available except through his dealer.
You all think it through, surf for better answers, and be ready to let the pro's do the work, because honestly, even a great powertrain mechanic knows he could be kinda weak on A/C, and it's better to let the other guy get it done right the first time.