I have 1999 v70 with approx 108k miles. Recently i noticed that when coming to a stop the rpm will drop to around 500 for a couple of seconds and then bounce back up to normal idling speed. At times it feels like th engine is about to stall out. Other than tha the car seems to drive normally. Any ideas.

Sounds like the torque converter lockup is not unlocking. This is a software issue and new software can be downloaded by your dealer. Common problem in 1999.

Klaus

My 2000 V70 w/AW5 tranny does this also, but only mildly so. You can just barely feel it as you come to a stop. The car has 92K on it (I just got it) and haven't yet flushed the transmission fluid as I am waiting to pick up a case of the Mobil ATF 3309 from a local distributor. Did the 2000's w/AW5 also have the software issue?

Thanks,

There could be any number of causes for this:

a vacuum leak somewhere
a dirty throttle body
general tune-up issues (plugs, air filter)

But it may also be related to the electronic throttle module in this model year. They're known to fail outright, usually at much lower mileage than you have. There's also a service campaign/recall on that part that has been very well documented on the web. Do a Google search for "Volvo S70 electronic throttle module recall" and you should come up with plenty of reading material.

--
Jim Rothe, '99 S70 T5M,
http://www.jimrothe.com/volvo/index.html