Did this car have r134a service connections already installed? Did you use an r134 manifold and guages?
If this system was still R12, how did you get the r134 into the system?
If this was originally an R12 system, and this was the first introduction of r134 into the system, there are other things that you should do.
At a minimum, you should remove as much oil from the compressor as possible and replace with ester oil, then evacuate, use r134 connection adapters and charge. The mineral oil originally used with R12 is not compatible with r134 and will knock out the compressor.
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