Looking at a steal of a buy on an '05 Saabaru (2.5 N/A) that has a strange knock between 2k & 3k RPM. No noise below, no noise above, runs smooth and pulls fine. Unknown maintenance (trade in). They say it happened suddenly during a test drive, no noise before.
From my searches, I'm optimistically thinking possibly a broken timing belt tensioner?
Anyone run into a RPM range specific knock before?