Creasingvermin1

Hey guys, I recently came into ownership of a 2010 C63 and trying to build it back to its original factory quality from what it is now. It is sitting right at 110k miles and has some noticeable problems (rumbling from 50km/hr- 100km/hr) and is trying to start to misfire on me very rarely. Some of the work I’ve done so far is the ROW air boxes, new spark plugs, already ordered the new factory spec fuel injectors. My question for you all (other than any advice or experiences you’ve had with the w204 platform that would be helpful) is if you had to plan the rebuild with budget in mind, what problems would you correct first? The eventual plan is to supercharge the vehicle after a transmission and engine rebuild, however that is going to be much further down the line after I finish up pharmacy school. (Also I’ve been told the head bolts have already been updated, I do not trust that in the slightest however and I’ve ordered weistecs updated ones.)
Thank you all so much!
-Zac

lo-fi

Fluid flushes if history unknown. All rubber suspension bits and mounts. I'm sure the shocks/struts are shot as well. Head bolts if not the updated ones. Cam adjuster plates and possibly lifters.

HLG600

The valve covers are easy to remove and you can check if the head bolts were updated.

crehop

Transmission fluid replacement/ radiator check fluid flush if needed/ spark plugs/ coils/ belts/pulleys/belt tensioner/ oil/ confirm bolts... thats about what I'd do with a new one then wait and see if anything else is bad. Once its all fixed to spec its very solid, just keep the oil changed.

skullbox15

If you are going to open the valve covers to check/replace the bolts I would do the seals as well. Top and front as they are cheap. Next point of failure could be the pulleys if they haven't been replaced.

IMfam0us

Add PCV, intake manifold bolts (one time use), and intake manifold gasket on your to do list, pcv starts to go out around that mileage. You can do it the same time you do injectors as those and the rail need to come off anyways.