I have a 06 altima that smokes a little bit while

two causes i think here either too much oil or worn piston riings and possibly valve guide seals,check the dipstick is the correct one and the top piece hasnt broke off so its going down too far ,this plastic top piece often breaks allowing the dipstick to go down too far or in extreme cases someone repairs it and then its not going down far enough

well black smoke means you are burning up engine oil. low idle means you have less compression. you might want to check your gaskets! does th engine oil level go down after a drive?

have the injectors checked for tip problems .

The BST engine in your Caddy is prone to a couple of design flaws that can cause the trouble you are experiencing. Certainly, it could be an injector but could also be down to timing or the camshaft sensor. If you haven't had the timing belt changed, it may have stretched a tiny bit and that's enough to cause the problems you have with lumpy idle. Timing is adjusted on the camshaft pulley - but tiny adjustments can make a big difference. The EGR valves are also prone to sticking causing black smoke. Hope that helps a bit.

Doesn't really matter with 200,000 miles and blue oil smoke.
Pull the motor out,then decide what to do.
You can break it down, if you really want to find the cause.
It still has to be rebuilt or replaced

You wasted your money on any auto part store product,
for any application.
You only go to the parts store for parts,no chemicals,no injector cleaner,
all unnecessary and nearly useless and sometime harmfull products.

CHANGE FUEL FILTER.HAVE FUEL PRESSURE CHECK AND HAVE THE IGNITION TIMING CHECK.TIMING COULD BE OFF A LITTLE.HAVE IDLE SPEED CHECK ALSO.

If there is no loss of Coolant, which is a sign of Head gasket failure to the combustion area, which generates white smoke, I would recommend after 4000 miles of your mileage alone, a complete Service of Engine Oil and filter, AIR filter and Fuel filter.
An inexpensive way to find a recurring combustion problem, At 60k miles, the Spark plugs should still be good, but pull them anyway, just to confirm.
Regards,DT

85,000 miles. I hope their not the original spark plugs,air filter,gas filter,etc. Your flerting with break down maintanance.
If you haven't flushed the Transmission,Power Steering,Brake Fluid,Coolant,Etc,your also going to be sorry down the road,and have some major repair bills.

What color is the smoke? White smoke is moisture/steam - which can indicate coolant is leaking into the engine (head gasket going bad).
Have you noticed your coolant level going down? Check the level in the overflow tank and the radiator each day (after the car has sat for several hours) and see if it slowly goes down.

It sounds normal white smoke comes from moisture in the air as it's burned and the air temprature is different. it creates steam they gray smoke is a little harder to decide what it is, normally gray smoke is related to oil burning and black is over fuel, depending on how many miles it has on it it could have bad valve guide seals but would not worry about it.