zeaq

Hi,
I just notice a few times already after driving for like an hour plus or so and whenever i stop at a traffic lights junction i would notice white/greyish smoke from the tail pipes. Once i accelerate; it will be gone.So I let it idle at the parking lot for a while and observe the tailpipes. No smoke.
Car has 54 000km and its a 2012 model
Coolant level is fine and car drive fine
In my mind greyish/white smoke during waiting at traffic lights:
1)Head gasket?
2) Valve seals?
3) Piston rings?

I also ask this at the C63 Facebook page and one suggested it could be a injectors?




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G_Money

What's your oil level looking like? Could be valve stem seals too. Had the same symptoms on my old E55 and thats what it ended up being. That was over 100k-110k miles tho.

zeaq

I change my oil every 7k KM now. At 1st i followed the dealers oil change intervals which is 10k. I recall by 8k KM i would get "refill engine oil at next refilling warning" and i top it up. By 7k the Oil level would be between the low level and top mark.So i usually change the oil by 7k.
Valve steam seals. I guess whole engine needs to be out to change it?😢

Solo wing

Heads need to be removed, which makes up 60-70 % of the engine removal process. If I were to remove the heads, It will be complete engine removal and overhaul.
AMG says ~ 0.8 Liters per 1000km (0.85 Qt per 621 miles) is acceptable for the M156, anything more and it requires a repair.

Good luck.

roadkillrob

I believe the heads can come off with the engine in, but in a shop may be easier to just pull the cradle out to do the work time wise, exhaust manifolds are a pain to pull off in the car that is what makes pulling the heads a bit slow in the car. I guess the risk is you pull the heads in the car and then find an issue with a ring or piston and have to pull the ending then anyway.

zeaq

Thanks for the reply.But before i do any decision.Next mth i will bring to the dealer or indy and ask them to do checking 1st too see what it is.

I'll keep on driving it though.