Hey everyone, newb here looking for advice. Have a 2003 A$ with 118k on it. last week noticed huge plume of smoke from exhaust as I was driving, white/grey color. It went away within a matter of a minute. Since then, two times the same thing has occured. I notice it happening at higher rpm, if i stay under 2.5 it doesnt happpen. When it starts to smoke I also hear a clicking sound from under the hood. Took it in for service and p0411 and p0135 came up as error codes. Full synthetic oil change, mini sevice was then done. Today it did it again, about 4 days after I had it in. Any advice as to what to do or what this could possibly be? I fear it's a blown hg or turbo and shiver to think what the costs will be.. I appreciate any input..