I want to tune up my S4 for the summer. Currently getting 18 hw driving and 16 city... I think its time for a tune up.
Any suggestions on what to change and replace? (Plugs, fuel filter, air filter,seafoam)
Am i missing anything?

 

replacing the MAF helps a lot w/ mpg too. everything else you mentioned is right on the money!

http://www.ecstuning.com/Audi-B5_S4-...gine/ES248498/

boost leak test never hurts.

 

I wonder if the MAF is OEM in the kit?
I just bought a used one not too long a lot because my last one was done. MAF can just be cleaned with spray and MAP as well...

 

yup its the oem one. they have two kits depending on year of b5 s4.