02-15-2016, 07:12 PM
If you don't see any oil, it could be hitting the exhaust manifold or exhaust pipe and burning, making smoke. If that's happening, it's turning into caked carbon on whatever hot spot it's hitting and is no longer liquid. That happened on our Subaru, couldn't figure it out. It was using oil, but not dripping anywhere, but we could smell it sometimes inside the car when the heater was on.