I cut the AC on for the first time since last summer today and it was blowing hot air.so went and got a can of refrigerant and put it in while retrofitting everythign to 134a. Anyway...AC blew cold as hell again so i thought i acheived victory only to get in my car today and try it out and it was again blowing hot. Somehow ive got a huge leak somewhere. So my question is ...What are the usual suspects when it leaks out overnight like that? Should i buy the red dye stuff ? What is your experience in dealing with the most common leak areas in our Z's AC system. later, Roger