Volvo 240 Engine Noise Diagnosis Help

[dowst]

Very recently acquired a very nice 1992 240 Wagon with ~220000 for my wife (our second!). Car had been religiously maintained by the dealership (3k mile oil change intervals, extensive service history--all major services performed until car was parked). Car drives very well (recent complete front end, drives tight!), and after a throttle body clean, oil change and a Seafoam treatment though vaccuum line and gas runs very well.

The only issue is a rattle/knock noise coming from what seems to be the drivers side, lower in the engine bay. I've linked to a Youtube video I took today before cleaning the throttle body and running Seafoam through the intake. As in the video, seems to occur mostly at deceleration after revving, but also at certain RPMS (no tach, so can't specify)during let-off of the throttle. At idle it seems to be more of an inconsistent slight/quiet tapping noise. It seems to be most prevalent at cold start, but never totally goes away at operating temperature. When heard in the cabin, it sounds like its originating from fore of the transmission well.

Here's the link to the video that you can clearly hear the rattle:



Any suggestions or ideas would be greatly appriciated!

Many Thanks,

A. Dowst