'02 Ford Taurus SES does not smoke white or blue or black out the tailpipe, it does not have a leak when I park, the oil light in dash does not come on, it has 177000 miles, and I don’t know why it uses up a quart a month. Any clues?
You can burn oil without seeing the smoke. The cat will eat it.
You can leak oil without it dripping on the ground. There are plenty of places for it to pool up and cling to and slowly turn to greasy sludge.
Using a quart a month doesn’t say anything. Translate that to a quart per XX miles and then folks can tell you whether its a cause of concern or not.
Either way, check your PCV valve. They’re cheap & easy to replace, and if they plug up will lead to excess oil consumption.