code 66 mystery

[atv087]

i have a code 66 on my oldsmobile eighty eight royale 1992 and i had my ac compressor changed over the summer and it was fine after that so i dont know why im getting a Low A/C Refrigerant Charge. my car stalls and jerks until it warms up

any ideas what could be bad

[maxwedge]

Low refrigerant, but this should not cause stalling, different issue.

[atv087]

so whatever is making my car run like shit isnt anything on the belt

[maxwedge]

The stalling and jerking cold, should be scanned cold when this is happening, looking for coolant temp sensor problems or other related issues that normally pop up only when cold.