smell problem

Exhaust leak or fumes entering cabin area, if you're running rich could have more gas in fumes. Another source for irritating fumes is a leaky evap coil in the heater box. That will come through the vents if you run the blower motor. Then again you may just have one or more leaky fuel injectors, accumulating gas fumes under the hood. You should also check your cabin filter.

What Engine...Mileage? Any Warning Lights ON or Flashing?

What ever the cause is you had better fix it right away because you have a serious safety issue.

Have your fuel dampner checked - known issue