Hi, I have a 2000s s80, 2.9 non turbo,
My wife drives 99% of the time, she said it bucks, ok, I drives never see it, she says it still happens, itgoes to volvo dealership, . I suggest the ETM as the recall exists and mine is still origional. they cannot replicate,find no etm trouble code, they even tray a new etm to see if car behave different. no luck.

well today, it happended to me, in high gear, around town, pretty steady on gas, not really accelerating, car starts bucking, tachometer jump maybe 250 rpm, each time, as long as I stayed at this rpm it hapened, if I slowed, below 2000 went away, accelerated about 2500, no issue.
It did not seem like an engine miss/ skip.
I remember the old gm cars and lock up torque convereter when they first came out and this reminds me of that, almost seems like the convereter locking and unlocking, otherwize trans see//ms fine. (Ihave done 3 fluid changes over the life, and wife does not beat on it, so I think trans itself is ok.)

Anyone seen this? thank you for your time,

Dave

 

Haven't really seen that before. Maybe you can get someone from the Dealer to ride with you and show them what it is doing.