My wife brought our vehicle in for an AC check last week as it was no longer blowing cold. The shop performed an electronic leak test and found no detectable leaks. They evacuated & recharged the system, (including addition of sealant, oil & dye) and "cleaned debris" out of the compressor. The vehicle passed a 20 minute vacuum leak down test.
The AC worked great for about a week, then lost its cool almost immediately. The shop is now saying that a black light leak test has found dye on the evaporator core outlet indicating that a new core is needed - cost $1200.
The shop is claiming that sometimes a re-pressurized system will cause weak parts to fail (ie, evaporator core). I feel that they simply did a poor job of testing during the first visit, and charged for unnecessary services that didn't resolve the problem.
Would a core go that quickly without any warnings or indications during testing? Do you think a black light test done on the first visit would have identified the core as the problem?
Thanks