[gabecz]

Hi
i have smoke (?) coming out from under the hood. Barely noticeable, only happened just today (about a week after doing service B where they said it's all ok)
I have a condition, I can't smell. So I'll have to ask someone if it's smoke or steam. There's a 'wet' looking tube that most likely is causing it. It is marked on the pictures.
Any suggestion? (almost feels like a mispoured break fluid but since only that tube is shiny it's unlikely)
the first pic shows where i put my phone to take the 2nd pic.
if i'd seen a 'blueprint' of the engine i could tell what that tube is. i wish i could describe it better.
there was not one drop of fluid under the car. ever.
thank you so much.

 

[gabecz]

i found a picture of an engine taken out. so that's the tube that looks 'wet' not the thick metal one in the front but that skinnier behind it.

 

[Swedish Steven]

I think you have a leak at the camshaft expansions plugs. Common fault on 280/350 and with the symthom you describe. Check this out: Oil Leak, Possibly cam shaft expansion plug?

 

[Gbarringer100]

I think Steven nailed it, expansion plugs. There are 3 of them that are not that costly to replace. Pry out, clean the opening, and pop them in.

 

[gabecz]

i checked, and yes around those round things are fresh oil spots/drips
couldn't find the 'big one' though. only the two 30mm on both side of the top of the engine. but now that i look at the picture of the taken out engine it's pretty obvious where it is mine has screws on it and it's completely dry around its rim.
is it enough to replace the two little ones if the big one is dry as desert?
thanks again. part from amazon (original mb part) is 9 bucks for a pair.

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i hope it's not "original" but made in Stuttgart (or in a mb factory for real)

is it coming with the rubber band/gasket? does it have one? or should it just click in and done?

 

[Gbarringer100]

No gasket; make sure the opening is clean. They snap in with some hard pressure. You can use a small screwdriver to pry out the plug. Most likely, it is the large plug that is leaking.

 

[Ragnar]

i checked, and yes around those round things are fresh oil spots/drips
couldn't find the 'big one' though. only the two 30mm on both side of the top of the engine. but now that i look at the picture of the taken out engine it's pretty obvious where it is mine has screws on it and it's completely dry around its rim.
is it enough to replace the two little ones if the big one is dry as desert?

The big one is a vacuum pump on the 280. I think the big plug is only present on the 350 and 55 AMG, they don't have that pump.
Be aware that the plugs have teeth that hold them in place. Those can be brittle with age and break off when you pry the plugs out.
When I did mine I had to fish a couple of teeth out of the engine with tweezers.

These are mine, from when I did the repair two years ago. The three old ones and a new one at the far right. The new ones have a different style of rubber gasket that supposedly isn't as prone to leaking as the old one.

 

[gabecz]

thanks everyone
i popped in the pair of the small ones, and there seem to be no more smoke, but the leftover burning off the hot parts of the engine. i still can feel "fresh" oil if i reach in under the passenger side plug though. i hope it is only the 'rest' that is still there.
i started a new thread about a check engine light & P0496 code. can these two be related?