i have a 97 ford f150 with the 4.2l i changed the plugs and wires on it and then when i fired it up it started smoking it runs smooth and better than b4 i changed the plugs no engine light so whats wrong with it

 

Did it quit smoking after a few minutes?

 

yeah it did but that still worries me

 

Was there any oil on the outside of the spark plugs when you removed them? If so, then the oil may have drained into the combustion chamber. When you cranked it up, it burned it away. Now it's gone. But if this is the case then you have an oil leak somewhere on the outside of the engine.
Just an idea....