I have a 2002 Subaru Outback. Everytime the weather is really cold, (like 20 degrees or below according to my dashboard reading)when I start my car, there is a strong odor, (of fuel I think) that fills the interior of the car as it warms up. It seems to be coming through the air vents but as I need them on to defrost and warm up the car, the smell gets stronger. It only happens in the cold though. If its above freezing there is no smell. What could be causing this problem?
There is a known issue with gasoline odor in very low temperature conditions with some Subaru models of this era. The problem is the result of fuel line clamps that loosen slightly under low temperature conditions.
Your Subaru dealer should be familiar with this problem, and it is possible that there was a recall on your car as a result of the problem. If so, then repairs will be free-of-charge. Even if it is something that you have to pay for, gasoline fumes are not something that can be ignored.
Have the fuel injector O-rings inspected for leaks when the engine is started cold. If any are leaking gas can end up on top of the engine where the vapors can get drawn into the vent system.