Thanks - you were right. My car is a 93, so it doesn't seem to be covered. However, I will definitely tell them to check the throttle body in case it's gotten clogged or sticky. Would still welcome any comments!

(from consumer reports - recall report)

Volvo 850 and 960 series cars '96-'97

Engine may not slow to idle when accelerator is released.

Models:

13,221 late '96 and early '97 sedans and station wagons made 4/96-7/96. Affected cars can be identified by last six digits of vehicle identification number. 850 models bear numbers 256997 to 311340; 338213 to 380371; 332305 to 376485; and 339561 to 372831 (numbers run sequentially). 960 models bear numbers 036243 to 039442 and 098612 to 107701.

What to do:

Have dealer replace throttle body in fuel system.