Hey car people...how long can a vehicle survive with an oil burning issue?

I drove my old car for about 12 months with the same issue. They had to keep cleaning the leaking oil off as it stank. Finally the smoke starting pluming out of the exhaust and it died a miserable death. It’s the 3rd car I’ve killed from my inability to put the correct amount of oil in a car

It has worn/cracked piston ring(s). They will run, but with reduced power output for quite a while but you have to keep them full of oil. If you run it dry it will die a quick death.
It is probably not worth fixing on a 20 year old car.

It will limp for a while. With regular patch up jobs.

It is perfectly possible to run a diesel engine on old sump oil, which would give the emissions you witnessed. It would not however be road legal or in any way environmentally friendly. There are many ways in which lubricating oil can get into the combustion chambers some of which are more serious than others.

Depends on whether they keep topping up the oil ...

I know of a 98 saturn that I'll bet money will double its 260000 miles. As long as the current owner adds a little oil evey few days. And I'm pretty sure my 04 jeep that I'm driving now was burning oil before I bought it 8 years ago.

It depends on where the oil is coming from. But if you keep it topped up you might go a long time. Unless you fall foul of the police or an EPA check.

It's not about how long it can survive. You must have it fixed ASAP. It can cost you a lot more later as it will surely cause major damage to the engine.

I'd suspect if it hasn't seized by now it will soon enough

You could drive a long time like that. Check your oil often to make sure it's not too low. You can also add some additive that helps with oil burning!

Until it won’t pass a smog test.