so i was throwing a maf code which was 25 and i replaced it with a new used one. code went away but now my car idles at 1500 rpm on cold start ups in park, and 1000 rpm in drive/reverse. any idea what could be wrong?

and i also notice some smoke coming out from the intake engine area. couldn't really tell where though??? any help? and my coolant light has been coming on??? help please