Hi All,

I have a 2003 6.0 w/ 138k miles. I have not done anything to it but change the tranny fluid at 70k and change the oil anf fuel filters regularly.

Recently, it has been starting rough and I get some black smoke for the first 20 seconds or so. One warmed up it seems to not have the powewr it used to. I get between 15-18 mpg

I have been running an SCT economy tune for at least 50k miles.

Is there any other general maintenance I should do?

 

if it hasn't had the newest flash i would get it done and should fix your problem.

 

get the inductive heating flash if you don't have it...maybe try some Hot Shots Secret if it turns out to be injector issues before you replace (HSS gives your money back if it doesn't cure it)...also you didn't mention air filter, how is that doing?