Blue smoke means it's burning oil, and white smoke means there's water in the exhaust.

Added together, you may have a blown head gasket. Although it's an expensive fault, leaving it in the hope of improvement (it will not fix itself and there is no quick fix alternative) will just add more cost to an expensive repair.

I sincerely hope that I'm wrong, but you need to get the vehicle to a garage that you trust asap and get them to do a quick cheap "sniff test" on the engine coolant. It's also possible that your engine's turbocharger has failed; this possibility is stronger if you've stretched the oil or filter changes, used incorrect oil or poor quality filters, or if you have turned the engine off immediately after a hard run (all turbocharged engines should be left to idle for around a minute before turning off after either a long high speed run, a steep hill under load or when towing a heavy trailer). A failed turbocharger is also expensive but there's less labour involved.

I hope that you have found my reply to be of use; please take a moment to rate my answer.