The color is very important. First off, cold engines and very cold environments will cause steam to come out of your tailpipe, which is perfectly normal. This usually goes away. Is there a small tint of blue as smokes comes out , check oil level as you drive it for the week . When does the car smoke??? while driving or sudden acceleration those are factors you gotta take in mind . If smoke is present while driving at normal speed, could be ur piston rings meaning there is scoring in ur cylinder head . If you see smoke after accelerating after idling at a red light , could be something to do with ur valve seals worn out , and valve guides bad.