A/C blows cold then hot then cold then...
 

'87 Coupe with the electronic A/C. I just had it converted to R134 thinking that being low on R12 might have been the problem. Set on "Auto", at any temp, the air blows cold for a bit then turns hot for a while, then back to cold, etc. Is there a module or sensor that is supposed to control and moderate the air temperature? Any help or suggestions will be appreciated.