1986 jaguar xj6 charging the ac it freezes on the low pressure side at the compressor and on the backside of the expansion valve high pressure line from expansion valve is neutral temp neither hot nor cold. Sound like a bad expansion valve?

 

first time I hear of a freezing situation like that in the Series 3 XJ-6 a/c.

what refrigerant is being used?

 

134a Converted from 12 a few years ago. No stop leak additives.