Hi, recently my passat has been making a weird metallic-like sound, I know that it's not the flywheel since that is on the other side right? Now it recently had an A/C job done could it be due? The car functions just fine.
What ended up being replaced was the compressor pulley as the inside plastic teeth were worn out, maybe they messed up in assembly or something.Maybe try removing the accessory belt and see if the sound goes away, if so you can isolate it to the A/C area. Did they replace the compressor with a new or used unit? Maybe the belt tensioner or A/C clutch?