[W126 Coupe] Rough idle in 560 SEC results

[Doug Gavin]

Tom Oelsner wrote:


> Hi Dick

> See Below

>  

>  

>

>     -----Original Message-----

>     *From:* mbcoupes-bounces at mbcoupes.com

>     [mailto:mbcoupes-bounces at mbcoupes.com]*On Behalf Of *Dick Spellman

>     *Sent:* Thursday, December 07, 2006 4:13 PM

>     *To:* Mercedes Coupes Mailing Lists

>     *Subject:* Re: [W126 Coupe] Is this a monovalve problem?

>

>     Hey Tom:

>

>     Could be mono-valve then again maybe not.  If you throw the temp

>     dial until it clicks in the red, do you get hot air?   Not until I

>     am standing still.   If you then throw it to click in blue do you

>     get cold air?   Yes  If you then throw it in the red but, not all

>     the way to the click do you get hot air?  Not if f I am driving. 

>

>     Another way to test the mono-valve(s) directly is to apply 12vdc

>     to the 2 pin terminal atop the valve and see if you get hot

>     air.   What current? Other possibilities are ignition switch, or

>     climate control head or possibly a sticking fresh air make up door

>     which would be the two vacuum element flap up under the passenger

>     dash.

>

>     Anyway, you need to test further and report your findings.  If you

>     are inclined, just pull the mono-valve head and see if it's 1.

>     fouled with sludge and 2. showing signs of a ruptured rubber

>     seal.  If sludge only clean and re-install, if ruptured, replace.

>     ($20-40 depending on where you buy MB stuff)  I figure I'll do it

>     when I am taking time off from work at the end of the month. 

>

>     Regards,

>

>     Dick

>     btw:  took a position this past summer in the Northeast for a

>     company with US hq's in Sunnyvale (home of fantastic sushi) and

>     world hq's in Kobi and Kyoto, Japan (home of world's best steak,

>     would you believe?)  Same field as before just doing more work for

>     the US govt as a result.  Having fun too.  Let me know how the new

>     job is going.

>

>     .toelsner at comcast.net wrote:

>

>>     Happy Holidaze to Everbody,

>>     Well it is finally getting cold enough to turn on the heater in

>>     the mornings...now here is the scenario.

>>     When the car warmed up enough to turn on the heater, it was only

>>     blowing mildly cool air no matter what the temp setting or what

>>     buttons were pressed.  Driving speed was 75-85 (hey this is CA). 

>>     As soon as I stopped at a light, the air blew HOT.  The next day

>>     I tried a variation...drove the car until warm, pulled over and

>>     waited to see if it blew hot air.  Air only remained mildly

>>     cool.  As soon as I started driving, it blew hot.  I turned down

>>     the temp until it blew cold and then turned up the temp...only

>>     got mildly warm.  At the same stop light as the previous day, it

>>     blew hot.  560SEC has around 165k miles on it.  Does this sound

>>     like a monovalve problem?

>>      

>>     btw..saw a great license plate on a new MBZ when in LA earlier

>>     this week...hys2pid..maybe it was hys2upid...I was dodging

>>     traffic when I saw it

>>      

>>     Tom Oelsner

>>

>>------------------------------------------------------------------------

>>

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>>W126 SEC Mailing List

>>Postings remain property of MB Coupes, L.L.C.

>>

>------------------------------------------------------------------------

>

>The MB Coupes Website!

>W126 SEC Mailing List

>Postings remain property of MB Coupes, L.L.C.

>

Several members recommended the product KB-44K for a rough idle in my 
560 SEC. I added one bottle ($25) to 20 gallons yesterday and within 40 
miles the car has improved. It's not perfect yet but it's only been 40 
miles at highway speeds so I'm very optimistic given the early results.

Thanks to the members that take the time to respond to the questions put 
forth by those of us that don't have the years of experience with these 
fine cars. The information is extremely helpful as in my case it might 
have been a trip down (and potentially still could be) the path of 
injector replacement or worse yet, fuel distributor replacement. Let's 
hope for the best result. Thanks

Doug
Houston, TX