[W126 Coupe] smoke on start up?

[Mister McGoo]

An opinion?  Don't worry about it.  The cold start injector is enrichening 
mixture for quick starting likely causing the black puff from a cold engine. 
  It is designed to only operate when starting the engine from cold.  It's 
normal.

Plus it sounds like you are getting a tiny bit of oil leak-by on the valve 
stem seals.  It is likely so minor it is only visible (blue) on start-up.

It is nothing you would do anything about unless it gets really bad, and 
then it would likely be valve guide time anyway.

It sounds to me like you are miles and miles away from that.  Relax and 
enjoy the car...

-Bellamy


>From: "Shayegan, Richard" <rishayegan at davidson.edu>
>Reply-To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
>To: "Mercedes Coupes Mailing Lists" <mbcoupes at mbcoupes.com>
>Subject: [W126 Coupe] smoke on start up?
>Date: Wed, 5 Oct 2005 22:17:10 -0400
>
>For a long time now (5 years or so) I've gotten a puff of black smoke
>out of the tailpipe when I cold (or cool) start the car. I basically
>ignored because last time I had the car in the shop, I showed the guy
>(he was replacing a leaky fuel line while I was on the road, but he was
>a good mechanic at a good dealer MB of Alexandria) and he said it's just
>age and not to worry about it. Well today when I cold started it I
>noticed the smoke looked like it might have been bluish. Cool starts
>still only do black smoke, and once started the car is fine (no smoke
>even at WOT, I'm getting good times for a 380, and it idles and runs
>like glass even with busted motor mounts and my starting problem has
>gone away, I guess I was too lean). What does this mean? I mean, clearly
>it means some seal is on it's way, but which seal would only burn oil on
>cold start (oil level is exactly where it is when I changed the oil 2000
>miles ago) and what's the reason behind my puff of black smoke on cool
>starts?
>Thanks,
>Richard
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