the concern is I believe first possible IMS bearing failure. Thus the less the engine is run the better off. The engine may be at this stage salvagable.
If the noise is coming from the front of the engine the IMS bearing becomes a less likely suspect.
One 'trick' to determine if the noise's source is inside or outside the engine is to remove the serpentine belt and start the engine and let it idle for a moment. This requires the noise be present at cold startup. Be sure you carefully note the direction the belt runs and its routing.
If the noise is not present with the belt removed the source of the noise is from an accessory drive or a belt idler roller bearing or a belt tensioner roller bearing.
If the belt has a sharp edge (the inside edge most likely but the outside edge should *not* be sharp either) an accessory drive shaft/bearing assembly has developed excessive play and the pulley is tilting slightly and the belt is mis-tracking and an edge is rubbing against the side of the drive's pulley.
You can give each accessory drive pulley and good wiggle test, checking for excessive end play, or radial play. If there is a bad one you might not recognize it at first cause the play can be a bit slight but one thing you can do is check all and develop a feel for what a tight accessory drive shaft and bearing feels like then you can better recognize the one with the play.
Without knowing the history of the car I can only make a WAG but it would be water pump. (My 02's water pump failed around the 170K mile mark.)
But check all accessory drives.
If the noise is still present then this suggests a chain tensioner or drive at the front of the engine. There is only one. The front of the IMS drives one of the head's exhaust cam which in turn drives the head's intake cam. (At the rear there is the crank to IMS chain drive with its guides/tensioners and the other IMS to head exhaust cam chain drive with its guides and tensioners.)
If the noise is present with the removed I'd urge you to shut off the engine, re-install the belt. Then button up the car and arrange to have it flat bedded -- with *no* engine running -- to a qualified shop and have the source of the noise diagnosed. You can tell the tech what you did. He'll likely start the engine and lift the car up in the air and underneath listen with a mechanic's stethescope and pinpoint the source of the noise.
Sincerely,
MarcW.