Bought my first E46 325i touring a few weeks ago. Previous owner had been chasing what he suspected was a "vacuum leak", causing a slight miss at cold start but otherwise drove well.
I got under yesterday to do the fuel filter and trans mounts. Took the cover off the fuel filter and sre enough the vacuum line is perished at the regulator. Take the filter off, replace the fuel lines and vacuum line while I'm there and finish up. Had the old fuel filter on my bench with black fuel and sediment coming out of it and that's when I realized the date on it was the build date of the e46.
22 years / 160000kms later.. yikes!