My 92 Sc400 with r12 is not blowing the same temperature the center right vent is blowing the coldest while the rest are blowing at a much warmer temperature at full blast they get somewhat cold but not as cold as the the middle right vent. I just got this car a week ago and had some spare r12 filled it with 2 cans not sure if i need three or not but it could definately stand to be colder in the day time its pretty cold at night but daytime is NO Bueno just good enough to ride with the windows up.

 

I have the same issue with my 93 SC300 with the vents also.I just charged it an it leaked out in 3 days. I have a bad leak somewhere. Does anyone know where the most comon leak maybe?