We’ve all smelled it at the gas station. However, if you smell raw gas when you are driving or before you start your car, check your gas cap. You may have overfilled the tank or left the gas cap loose. If the smell isn’t caused by either of these things, don’t risk driving. Turn the car off immediately. You may have a severed gas line or leaky fuel-injection system that needs professional auto care. Get a hold of your mechanic right away and have the problem diagnosed and fixed.