mannionr

Considering buying a CLS63 (2013 50k miles). Upon PPI check engine light came on and misfire in cylinder #6. To fix, came back with Oil in Engine harness, and they need to replace the cam sensors, spark plugs and clean the harness. Anyone else have this problem? A quick search shows a few results from 2010'ish, but what about the newer models?

Should I still consider the car, or run? Otherwise in great shape and clean.

Thanks

Racin_fool

Honestly when we do them, I also like to check the connectors at the injectors and see whether those are also soaked with oil. As for cleaning the harness, you will never get all of the oil out of it. If you start disconnecting things such as the injectors, cam sensors and engine control unit and find oil at each part, you definitely need to replace the engine harness as it will continue to seep out of the harness into the components causing shorts or sensor failure later down the road. Spark plugs are worth inspecting, and you might have them done when doing the rest of the repair, but unless its time for them to be replaced (age/mileage) i wouldnt worry about them.

mannionr

Thanks. So this is a pretty common occurrence? And if not cleaned well, it can basically fail all of the sensors in due time, including O2? That could get really expensive. What would the harness cost installed?

Racin_fool

the M276 (v6), the M278 (v8) and the amg M157 (v8) all have this issue.. has been an ongoing thing for the past few years
The engine harness is a ZM time or open time punch under warranty for these engines. There is no set time under warranty, so its up to the shop's discretion and (hopefully) honesty about their repairs, procedures and their techs.

6speeddave

Go ahead and have the shop replace the engine harness and tell them you'll pay full price for the car.