Yes, the oxygen sensors can indeed cause this problem, as I found out.
Mine was accompanied by the "emission service required" light, as
well.
See my post on the 99 S80 issues I had with these, and hold on to your
wallet if you plan on having the dealer replace these; mine ran almost
1800.00 to replace all 4 sensors on my S80, and it took three trips to
get it done completely.
(Two failed, then supposedly the other two failed...)
Of course mine may have just been an isolated incident and not typical
of most S80's from that year.
I know there are advantages to using the dealer, however o2 sensors are $170
each at Auto Zone and they are mode by Bosch, same folks who make the one in
that volvo box.
680 plus say 2 or 3 hrs time for diag and r&r (70/hr) and say a 25% parts
mark up is well under 1100. Volvos use a common fuel injection system and
any skilled techs who work on VW's or many Japanese cars have the skills and
equipment to dx a volvo too, to say nothing of BMW, Benz or Saab shops.
The independants also have no easy income from new customers, so they need
to make you happy first time every time. In addition the dealer tends not
to see older and less well maintained cars then dealer techs making an indy
a better place for old car repair--IMHO.
Look for a place that a guy (or woman) owns where S/He is there very day
either wrenching or in the office.
Nice NAPA or certs from whatever place insure nohing, but a shop that has a
constant and changing flow of cars of a complexity of at theast a Volvo (new
VW at a minimum I would think, or loads of older rice burners) seems like a
good bet to me.
Talk to the people, see if they like what they do, if they see a dificult
job as a mystery to figure out, a game rather then a headache.
YMMV
