I have a 1996 explorer 4.0.auto. this thing has me puzzled it runs perfect there is no codes pulling up , the issue I am having is 2 things the air intake has oil in it and the other thing it has been smoking bad but not all the time if you drive it a lot it stops but when you come to a stop it takes a few seconds and then the smoke starts and of what I can see it has a lot of white in it other than that it runs good , I need help bad on this one is anyone one has any advice please let me know , thanks

It sounds like you've got a worn engine.
Oil is blowing out because combustion pressure is seeping past the rings and into the crankcase. I don't know if it's rebuildable right now but if not addressed soon and correctly you could lose the engine completely.

I agree with CaptainRich. Sounds like bad rings.

Remove all of the spark plugs and check each cylinder's compression, both dry and wet. Record and analyze the results--that should send you in the right direction.