Motors don't smell if they are well sealed. So, I'm guessing that either you have a leak in the engine compartment or, maybe you mean it smells like exhaust but not the sulfuric, bad catalytic converter smell? I forget, what do you own? GTS? If you are saying it smells like exhaust, then one thing I'd suggest that I found to be the issue on my car is the cabin exhauster vents. The covers with the flaps in them had fallen away. You will find them in the left and right rear of the cabin/trunk/hatch area. They are supposed to let air out of the cabin though the vents outboard of the taillights but not let air in through there.