[W126 Coupe] rough idle

[Gerry Van Zandt]

Reman fuel heads (fuel distributors) in general are, I hate to say  
it, problematic -- even the rebuilds that Bosch themselves do. Your  
best solution -- and I know it is not cheap -- is to get a factory  
new unit from MB. Last time I checked they were over $2K from MB, but  
at least they have a warranty on them, and you know what you are  
getting.

This definitely sounds to me like a fuel distributor or related  
issue. My second guess is a vacuum leak -- similar deduction to you.  
Have you thoroughly checked out the ENTIRE vacuum system for leaks?

Cheers,
Gerry





On Aug 9, 2007, at 4:28 PM, mbcoupes-request at mbcoupes.com wrote:


> Message: 8

> Date: Thu, 9 Aug 2007 11:43:45 -0700

> From: "Tim Graney" <graneyt at americancylinderhead.com>

> Subject: Re: [W126 Coupe] rough idle

> To: "'Mercedes Coupes Mailing Lists'" <mbcoupes at mbcoupes.com>

> Message-ID: <000001c7dab5$37d06b10$7901a8c0 at timpc>

> Content-Type: text/plain; charset="us-ascii"

>

> I bought the FD from German Star...? I did replace all the rubber

> gaskets in the plenum. vacuum stays nice and steady but does hiccup

> every once in a while. I have looked till the cows come home for any

> vacuum leaks. where does one get the right spark plugs...these are  

> Bosch

> plugs. what gap should they be? Thanks again

>