>>>*K..Here is what is going on....You have a small coolant leak that is the type that tends to seal itself once the engine expands with heat.
Typically we find those to be a small crack, or a leak in #3 or #4 exhaust port, or a tiny head gasket leak..

Combined with that, the engine has been using oil for some time, in small amounts. Over time, coolant mixed with burnt oil residue creates an ash that builds up in the exhaust system. Once fully warmed up, medium to heavy throttle will disturb some of that ash, the result is brown smoke..
The blue is oil and the cause of the brown....No I am not crazy, just a little nuts...But I am also right..*LOL**

Time to fix it....*EB