Don't fool around with this. And don't let fumes accumulate in a closed garage. You may be hearing air bubbling into the gas tank through a pinhole leak.

Once the pressure equalizes and air stops bubbling in, gas may start weeping out. If you smell gas, this can be a potentially hazardous situation. I think you should get under there with a flashlight and look for wet spots, or get it to a mechanic immediately.

Good luck

Marty
'96 855T

Check for leaks under the car first.
Then:
Never fill the tank to the second or third click of the nozzle.
Check the gasket on the gas cap, it may be getting old and hard.
If you drive short trips and slow speeds, your charcoal cannister may be full uf unburned gas. Take the car out for a 30 minute run at 60+.

If all these fail, drop by a dealer and tell him you smell gas fumes in the garage and don't want the house to explode.

Klaus
--
98 V70Rawd(108Kmi), 95 854T(88K mi), 75 164E(173K mi)

Look under the car for leaks, the evaporation from the fuel in the tank should not fill your garage with fuel fumes even if the evaporation control is out of order. The idea is that the fumes shall be trapped in the charcoal canister.
Think I have seen someone report a broken tank on 850 here...

When you filled up your tank did you stop when the pump clicked off or did you "top it off". If you topped it off you could just be experiencing some expansion and overflow.

Second idea is that there was a recent recall on several years worth of 850's. Not sure if yours was covered.