[Shotimes] A/C Help?

[Mark Mucher]

Folks,
 
My '90 w/ETAC and R12 was having clutch gap problems so, a couple weeks ago,
I pulled out the last shim and it blew cold as hell..
 
Yesterday the A/C stopped dead in the middle of a ten mile trip.
 
I'll do the research and diags but I wondered if anyone could suggest what
the most likely cause could be, thus perhaps saving me a lot of grief.
 
I haven't done anything yet except to observe that it has never even tried
to blow cold since it stopped..
 
It's not blowing THAT hot. so it's not a blend door.
 
Electrical?
 
Loss of Freon?  (Why now?)
 
Can an ETAC self test help?
 
Any and all help appreciated.
 
Thanks,
 
Mark