Just curious if Volvo has a scheduled maint replacement on these things?
My car has about 110K miles on it. I threw some new plugs in it last week and seafoamed it for grins and giggles to see if I can restore any kick it may have lost over the miles.
Feels a little sluggish lately, but not overly. Maybe a slight boost leak somewhere possibly or just needs some upkeep. Seems like it is working a bit harder and shifting strange.

Usually PCV valves are an easy replacement and worth wild to do, but I read the symptoms are if you are getting pressure from the dipstick tube to replace. Any other reason to replace in these cars?

TCV maybe could be the problem?

Also how do you guys go about checking for boost leaks easily in these? Im used to turbos being up front and can just cap the compressor and feed compressed air in and listen for leaks.
Same thing on these? Or any easier methods then digging around out back and doing this technique?

I have some extra boost gauges sitting around I guess I could run a vac line into the car to see what the boost is looking like. I never installed a gauge because its stock and auto so I thought it was a waste.