Kim, Listening to a v4 is part of the art of driving them. I assume this is a new sound. Might be the fan bearing. Test by removing the fan belt and briefly running the engine. Fan won't turn, hence bearing won't make the noise if this is the culprit.(posted 8812 days ago)Have you ruled out valves?
Is the fanbelt tight? Could it be coming from the alternator?
Good luck with your quest. Come back and tell us what happened!
D.O'Connor--SaabSpot