Do you have alot of black soot around your tailpipe? Disconnect and plug the line to the AAP on the carb. Fixed my issue on my old 85 that was carbed. I used to have a pic, but don't anymore. It's the small rubber hose directly under the larger fuel inlet hose, connected at the carb. Little diaphram goes bad, and allows the extra fuel used only for cold start ups, continue to dump excess fuel. You are running too rich.

85 4Runner - With NEW Marlin 4.7 Gears!! It's a whole new beast!