Hello, all! Something strange is going on with Jody's idling. Engine drops to ~500RPM after shifting to park, or coasting for more than 1-2 seconds, but ONLY when the engine is fully warm. It started around this past April, and even stalled once; However, the issue was FAR less frequent then, and a lot of work was completed, since. If you don't know/remember, Jody is naturally aspirated (B5244S).

ALL of the following was completed AFTER this issue first occurred:

• Complete timing belt/water pump job completed this past May
• Spark plugs replaced less than 4K miles ago
• New engine air filter last month
• ETM & MAF cleaned twice within the past year (the second time being a few weeks ago)
• ZERO OBDII/VIDA DICE faults/codes
• PCV system is in excellent working order
• New alternator, and voltage regulator
• New serpentine belt
• There's really nothing else I can think of besides one occasionally squealing brake rotor

A video of the intermittent idling issue here: A video of my Magneti Marelli ETM being tested here:
Attached photo of the ETM, as well.


Also, Jody hit the 248K mile mark recently!

Anyways, suggestions? Thanks in advance!
Magneti Marelli ETM (2001 S60 NA)

 

Since there were no answers, I have done weeks of research, and found out a couple of things, in case you happen to stumble upon this thread while searching for a more definitive answer:

Many times, it may not be your ETM, MAF, or alternator, and my particular S60 2.4 NA does not have an IAC, as far as I know, but the problem could very well be the fuel injector o-rings due to aging. This also applies to many non-Volvo cars.

if you are uncertain about when your fuel injector o-rings were last replaced, be sure to have them checked, and replaced, if necessary. It can cause more serious issues later on. A video was posted showing the procedure with a P2 S60 (PCV Servicing).

Also, check your PCV valve, as well. This can be checked at least two different ways according to the second video.