Tin worm attack ...
AO Gold Member
Join Date: Jan 2003
Location: United Kingdom
On a cold morning the exhaust will appear to smoke, but it's condensation. The colder, the more "vapour".
If it's oil, then the old trick used to be to get the car up to working temperature and drive the car normally but at fairly high revs (say 3rd or 4th depending on the road, etc). Then drop the clutch and let the revs drop to idle, and coast a bit. Then hit the gas again, and if you get a nice grey-blue exhaust, you're burning oil.