How did you run the engine in ?, and what oil did you use ?, I've seen it loads with people being too gentle, and leads to bore glazing, it will always smoke for ever and day if this has happened, a common mistake.
What colour is the smoke, as that can make a difference.
Ecu's do not need to spray fuel into anything to cool on the overun, normally on ecu's that shut off they just then act as a compressor driven by the coasting engine, and so cool more than with fuel being present and generating heat!!
What is the co like as rich mixtures will lead to oil burning also.
tabetha