Dark blue smoke = running WAY to rich. Too much fuel, not enough air. Light blue smke = broken piston rings. Loss of compression and loss of power.
usually blue smoke is oil
It is caused by oil getting into the combustion chamber and burning off
The kelly blue book of a 2009 Nissan can vary by the model of the vehicle. If you have a Nissan Altima and a Nissan Maxima they are going to be different. You are also going to have to consider in the mileage and features.
Cold start
change the blue box maybe.
Too much pot down the intake.
your car leaked oil into the combustion chamber. blue smoke= burnt oil, the loss of power is from inproper combustion
No I don't think you should. It doesn't sound safe to me if I were you.
If your engine is blowing blue smoke your engine is burning oil.If the smoke is present on acceleration, the piston rings are bad.If smoke is present on deceleration, then the valve guide seals are bad.
There should be a reservior of blue stuff under the hood. just fill it to the line.
Engine oil could be running too rich or rings!
transfer pump psi too low