It's only done this a few times but once is too much. Usually when i'm in slow moving traffic. The engine revs up like i've got the gas floored. I either have to try to get it out of drive or turn off the engine. Scary stuff. It's only got 30K miles on it.
Anyone else experiencing this?

 

Sounds to me like a vacuum leak, try and snoop around for a leak in a hose or a loose connection somewhere. If you can do a smoke test, that works too

 

Thanks. Does the Volvo dealer do a smoke test for reasonable cost?

 

Dealers usually charge a 1 hour minimum for diagnostics but I think that's a good investment given they can do a full VIDA scan and if need be, run some tests on vacuum driven components. You may want to do your own self inspection first by doing a visual and then spray around the hoses and intake tubing with carb cleaner (or similar) to see if you find some gets sucked in and bumps the idle. You may also have a torn diaphram within a vacuum actuated device (like the PCV oil separator) that may not show up with a smoke test. Where the smoke tests excel are finding those hidden or out of reach places - I just had one done to find a small evap leak fault to find where the hose running to the canister split...

 

Update: took it to dealer in Huntsville AL. They did a smoke test and all was normal. They basically they said nothing was wrong.