the car smokes really bad when i first start it and when i rev it up when i first start it , it starts popping at 3000 but when warm no popping or smoking whats the problem?

my 93 mx3 after its warm idles below 500 rpms ?

i have been looking for a cheap motor 2 replace my old motor with in a 93 mx3 a 1.6 or 1.8

 

You seems a little confused about which way you want to go, mx3man?
From the sound of it though, I'd say a new engine might be the way.
The engine in it now seems to have a few different issues. Though you don't say what color the smoke is.
Black smoke = overly rich condition... in your case I would say something to do with the cold start system, or an over-active 5th injector, if the car has one.
Blue smoke= oil. If it goes away after a few seconds but comes back after the engine has idled for a minute or two then goes away again, it is probably bad valve guides and seals. If it is present all the time, bad piston rings and/or sludge clogging up the oil control rings. Bad rings are the better bet though.
White smoke= coolant getting into the combustion chamber, being burned and exiting through the exhaust.