Originally Posted by
scarry
Very poor workmanship there,a proper vacuum test with the right gear will certainly determine if the system has a leak.
A vacuum test is often a better and quicker test than a pressure test,but it wont pinpoint the leak.
Due to the difficulty removing the compresser,you are better trying to pinpoint the leak first.After 400 000Km,good chance the shaft seal is shagged.
Using good quality leak detectors,leaks are very rarely not found.
We do this type of work all day,but not Auto AC.