Give it a few days, and watch closely for oil leaking. Slip a flattened cardboard box under the car to catch any oil, so you can see it better. Even if it's fixed, the smell will probably hang in there a while, but if it continues after just a few days (or if it leaks at all) take it back in. They'll get nervous soon if there's a lemon law in your state, so you should find out if there is one and how many shots they get at the same problem before it's a lemon. At this point you can easily start pressuring, but if they've been helpful, you might wanna go easy. If they're up against a tough problem they might be doing the best they can at this point.
