Rough idle smoking after running a while
Sounds like it may need a tune-up, a going over, throttle body cleaning, checked for codes. The 02 sensor could be a cause.
What color smoke? Black is unburnt fuel, blue is oil and white is engine coolant(water).
Blue smoke is burning oil which probably means a worn engine. Try cleaning or replacing the PCV.
The rough idle may be from oil fouled spark plugs. Try installing hotter spark plugs if this is the case.
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