I’m getting smoke from the catalytic converter area on my 2001 Subaru Forester. The smoke smells of rubber or oil. I’ve only noticed it after the car has been driven up a long, steep incline of at least a couple of miles. I’ve never seen it happen after normal highway driving. The car runs fine, gas mileage is good, CE light is not on, 85K miles, regularly serviced.
One possibility is a leaking valve cover gasket, where the oil runs down to the exhaust system when the car is angled upward.
I agree with Lion.
Another possibility is that you’re burning oil under load. How many miles on this Subie?
A compression check may be in order. Post back with the results.