Why is there still white smoke coming from your exhaust of a 1993 Mitsubishi Diamante when you just had the engine replaced?

Or someone didn't do a proper job on the repacement engine and you've got a leaky head gasket.Answer

"Stuff" is still in the muffler and exhaust system.

Thick white smoke can also be the transmission oil being sucked to the engine. check your transmission oil as well.