About to take the Dive into the M156 Platform and i have watched a ton of M156 content to get myself up to speed enough to understand what I'm getting myself into. I have a few questions i was hoping to get clarified.

The car has been sitting for roughly 2 years as it was left at the shop after the cam adjusters went. We threw a jumper pack on the battery and the car fired right up. The guy was reving the car up a bit to keep it running as he said its out of timing, and wouldn't idle. It made the typical cam adjuster noise at start up then quickly went away once oil pressure built up. He let it run for no more then about 30 seconds. It didn't seem like it wanted to idle properly due to timing, and he said it cant be driven because the car will "Buck".

Fair enough, However my question is directly related to the timing issue. If the cam adjusters are bad, does that also directly effect the timing as well, or am i looking at a separate issue? I've heard of cam adjusters going bad but the car is still drivable, although not advised.

My plan is to rebuild the entire top end, less removing the heads. Head bolts, Cam adjusters, cams, lifters, Pretty much everything to refresh the top end.

The last thing i want to have happen is to tow this back to the shop, do all this work, only to have bent valve or something worse. In Everyones expert opinion who has experience with this, i'd love for you to chime in.

I also purchased a borescope to inspect the pistons once i remove the plugs.

2009 C63 with roughly 133K and was serviced at the same shop by the same tech since 30K. The car is rough, but i'm getting it at a good price so i know that i won't get killed on it if in fact it goes south. However I'm hoping to rebuild the top end and be ready to go.

Appreciate any thoughts or comments.

- Joe

 

Whoops, wrong section...Mods please move to W204 section. Thank you

 

Whats the price? I think it's more than just the adjusters/cam phaser plates if it won't run, but I would budget inspecting the timing guides/chain/timing. Buy a scanner before you throw thousands of parts into it. The adjusters/plates going out typically just gives you yeah, startup noise and if its gone really far it'll devolve into rough idling so you're on the right track.