What about: "The fire caused a lot of smoke"? Or is demasiado always too much of something?
"Smoky" would be more like "humoso" or "lleno de humo"; I think the point here was "demasiado"..
I think humo is steam and there is a difference. Fumar is smoke but i guess its regional
"The fire made too much smoke" is cumbersome; "the fire smoked too much" is better english. Analogous to "it rained today" (English) rather "than the day made rain" (literal Spanish). I hope this comment doesn't constitute clutter.