My buddy driving behind me noticed a single puff of blue smoke from the exhaust during a hard acceleration. I read somewhere that indicates the engine is worn but my car only has 18K miles and I rarely drive hard. Is this something I need to worry about and should I take it to the dealer?

 

In general:

- white smoke indicates engine coolant
- black smoke indicates excess fuel
- blue smoke indicates oil

If it's just a small, single puff, I wouldn't be too concerned. It might be a valve guide seal that's allowing a little oil to get pulled past it in cruise mode, when engine vacuum is fairly high. Then, when you hit the gas, the vacuum rises to zero and the oil is quickly burned. Does it emit any blue smoke when the car decelerates from a high RPM blast with the throttle closed?

 

I have gone from driving my car from every other day to once every two weeks and have noticed that when I start it up it emits some white smoke but after it is warmed up it looks fine. Wonder if it is just from the cold weather. I have kept my gas tank over half.

 

you might have a oil leak.......get it checked out

 

If it only does it after long idle periods, it's probably just condensation. I wouldn't worry about it.

 

Sometimes i believe that when you get on the car real hard, it sort of cleans some built up particals out of the engine, thats just what i think though.

 

The mb intercooler is known to be weak and start to leak. The C32 I use for some road racing had a fairly large leak and it was sending coolant into the motor thought the intake. The leaking intercooler had coated the intake make the intake runners become over half clogged with dried up coolant ( a nice dark yellow oooozzzing goo! ).

Some people say that the intercooler leak can have coolant leak as the car sits parked and then when you turn the car on the coolant that has leaked out gets burnt in the combustion chamber and is expelled as a bit of white smoke at start up.

There is a thread building in the C32 forum with this topic. The intercooler cores are basically the same for the C32 and V8k motors (just different sizes) so the 55k's likely have this same weakness. A new cooler is about 2k on a c32 and likely more on a V8k.

Just a thought…


As for having blue smoke issues with the car, I know my SL55 has had periods where it puffs blue smoke at start up but I hear the galleys for the oil to travel though the head can become clogged in the M113 motors. Sometimes they clean themselves out and others they require dealership intervention.

 

i got the same issue with my e63 when i turn it on it blows out a white cloud of smoke than it is fine. when i drive it it drives normal my close friend who is a mechanic says it could be my head gasket but idk if its that bcuzz a head gasket shot the car can not move so anyone can help me out

 

Hello,

I’ve recently bought an A45 W176 and when the engine is warm (above 75degC) and only when it’s warm, the car emits blue smoke on overrun almost exactly as described below.

I didn’t notice this when I test drove the car because the engine temperature never reached above 75 degC. This was actually as a result of the thermostat being stuck open. The EML light came up on day 2 of ownership and the stat has been replaced. Since replacing the stat the engine runs at correct temperature about 94degC but now has this smoking problem.

there doesn’t seem to be any loss in power and there isn’t any nasty knocking noises (piston slap).

my concern is that it is Piston Rings or possibly valve stem seals.

I should add that the car is de-catted (not by me)

Any help would be much appreciated.

thank you.