The person before me converted the ac system over to 134a in my 91. I am not sure what oil he used and i cant get ahold of him to see what he used. What type of oil should I use in the system? the system is completly discharged so i need to pull a vacuum on it. its just when i took off the low side it still had some pressure(not much) so some oil spirted out that i think i need to replace. is there any way to test what type it is? or should I just put ester oil in it?

 

Depends on how it was converted. R-12 and R-134a use completely different oils. In this case, I would just look for a R-12 replacement with oil, kinda like the ones they sell at Wal-Mart.

 

wel theres 3, the stuff that works with r12, the PAG oil that works with 134a and Ester works with both from what i remember reading. if ester oil works with both, should I just use that? not much oil came out tho.