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  Topic Review (Newest First)
Today 02:10 PM
H.D. Gentlemen, maybe you should really contemplate doing what I said in post 19:
Quote:
Originally Posted by H.D. View Post
... “adjustments via adjustment tower should be done only in order to readjust a deviated EHA operating range according to EHA current / duty cycle … and only if all potential problems that cause the deviation have been checked and, if necessary, fixed or manufacturing tolerances of replacement parts require it ! … Maybe it wouldn‘t be a bad idea to print that sentence on adhesive film and stick it somewhere clearly visible in CIS-E car‘s engine bays. …
… and really stick that sentence somewhere clearly visible in your engine bays. …

You say that, from all you have read “the lambda screw should not be turned with the engine running“. That tells me that you've probably not read my Lambda control thread that I mentioned in posts 19, 22 & 32. … In that thread I explained under “Adjustment procedures“ in post 2, that the adjustment is always done while the engine is running at idle speed !

And again:
Before touching that adjustment screw, I warmly recommend to follow the above quote ! … But this is not my thread and what you (suggest to) do is up to you, of course. I‘ll not further interfere. …

H.D.
Today 12:26 PM
lesguy JR420: From what I see in the pic, the anti tamper portion was removed from the tower, so yes, appears at some point and adjustment was made via that adjustment allen head inside the tower.

HD is giving you the correct guidance. And rumb's guidance is good as well

I'd suggest not touching the EHA screw

I also suggest that IF you touch the towers allen, you do it with engine off and make a TINY change that you track. That way if the results arent positive, you can easily put it back to where it was before you touched it.
Also, after you make any change? I suggest driving it for a few miles, turn ac on, turn ac off, go on the highway, go in stop and go, etc. Let the system fully adapt to the tiny change you make. Then make your decision as to whether any improvement, was made.
Today 11:06 AM
rumb From all I have read the lambda screw should not be turned with the engine running. adjust in 1/8th or 1/16th turns and then measure again.

Personally I would put the EHA back where your found it and then read and adjust your duty cycle until that is in spec.
Today 09:22 AM
H.D.
Quote:
Originally Posted by JR420 View Post
... now for certain after a few more miles I can say an adjustment is needed. ...
I don‘t know, what “adjustment“ you have in mind, but before you touch adjustment screws I recommend to mind what I said in posts 19, 22, 26, 32 & 37:

Quote:
Originally Posted by H.D. View Post
... adjustments via adjustment tower should be done only in order to readjust a deviated EHA operating range according to EHA current / duty cycle … and only if all potential problems that cause the deviation have been checked and, if necessary, fixed or manufacturing tolerances of replacement parts require it ! ...
Quote:
Originally Posted by H.D. View Post
... old-fashioned as I am when it comes to troubleshooting and a number of other things ... I would do what I usually do before I touch any adjustment screws or replace any parts, namely test & diagnose ...
Quote:
Originally Posted by H.D. View Post
... CIS-E engine issues in general should be addressed by respective troubleshooting processes instead of by tampering with the Lambda adjustment screw, let alone the EHA adjustment screw. … Only if all respective potential fuel combustion affecting causes (which already a simple duty cycle check can point to) are checked and, if necessary, fixed, changing the setting of the Lambda adjustment screw (solely according to duty cycle or, better, EHA current !) is in order. ...
Quote:
Originally Posted by H.D. View Post
... the purpose of a duty cycle check is to get diagnostic information. Unprofessional tampering with the Lambda and/or EHA screw(s) distorts and ruins that information. … … Only if both of these screws have never been unprofessionally tampered with, the duty cycle provides reliable & valuable diagnostic information !
If you don‘t know whether one or both of these screws [Lambda adjustment screw & EHA adjustment screw] has/have been tampered with, a deviated duty cycle either points to specific fuel combustion affecting problems, or it shows that one or both of these screws has/have been tampered with. The problem is that you can not tell which of these two is the case … which takes you to that point in post 40 of https://www.benzworld.org/forums/w12...uty-cycle.html, where I said:
“... without at least knowing exactly how far in which direction the adjustment screw has been turned, valuable diagnostic information is gone for good (!) and everything that has an effect on fuel combustion (see examples under “Please note“ in post #2) has to be checked first before further touching the adjustment screw, in order to reliably restore a proper condition of the system. ...“
Quote:
Originally Posted by H.D. View Post
... As explained in my Lambda control thread, with the Lambda adjustment screw … (I recommend to not even think of it as “mixture screw“, for reasons I explained in that thread) … turned according to anything other than EHA current (respectively duty cycle) without knowing what the EHA current (respectively the duty cycle) was before it was turned or how far exactly in what direction it has been turned, the duty cycle‘s diagnostic information is gone for good. ...
H.D.

P.S.: Without email notifications and the forum not functioning properly anymore (at least not on my smartphones) I may not notice new posts until I log in via PC, which I do only occasionally.
07-16-2019 05:49 PM
JR420 Second update - can say now for certain after a few more miles I can say an adjustment is needed. Runs exceptionally well under throttle, but not the smoothest idle. I should have paid attention to.this, but it would appear as though the throttle mixture was adjusted previously correct?

Vehicle had rough idle when I bought it so wouldn't be surprised. Throttle plate does seem to have appropriate play before hitting plunger (not 100% certain)

Makes me wonder about EHA.
07-13-2019 11:46 AM
JR420 Update - Finally received back Fuel Distributor and test results of my injectors. 6 of 8 injectors failed either leak down, trigger or spray. Old diaphragm also appeared to have a number of pin holes and was badly worn. Put FD back on, new injectors and rest of hoses etc back together last evening. Did not jump fuel pump due to being able to see pic of my FD tested on flow bench from rebuilder. Within three or 4 30 second cranks it fired up. Few minor adjustments with stubborn to connect hoses that I thought were connected and it was time for a test drive.


So far I've put about 8 or so miles on it, not quite ready to say it runs perfectly just yet however the difference in throttle response and overall power is remarkable. I intend to put some more miles on it as I suspect there may be some air in the line going to the cold start injector perhaps and/or maybe some other air bubbles in a line or two that need to be worked through. Overall it's a big improvement! Will update with a bit more time on motor.

Side note I was able to find the throttle was not opening up fully and with a quick adjustment to the 10m bolt on the throttle bracket coming out of the firewall it's amazing how much more top end there is as well as proper trans kickdown.
07-07-2019 01:07 PM
lesguy Thanks. (Again)

Thinking at this price, won’t hurt to purchase and test. Even if the FPR currently in the car is good, would not hurt to have this as spare? https://rover.ebay.com/rover/0/0/0?m...2F163402043245
07-07-2019 11:31 AM
H.D.
Quote:
Originally Posted by lesguy View Post
... is my full throttle no upshift from 2-3 possibly related to my fuel system? ...
Only in as much as the fuel pump relay is involved, since it contains the kickdown shutoff function. As Heikkif mentions, it could be that either the rev limiter (fuel pump power cut-off) cuts in too early or the kick-down shut-off does not take place as it should 200 rpm below the rev limit.

You could either do what luckymike suggests, or you could check (easiest at terminal 9 of connector X26) if the (battery)voltage disappears at about 5600 rpm.

H.D.
07-07-2019 04:37 AM
Heikkif Maybe the rev limiter cuts in too early as fuel pump relay should shut off kick down at 5800 RPM. Anyhow fuel pump relay should shut off kick down if that was your question. As one releases pedal from kick down there is not happpening anything at the bowden cable or throttle linkages before kick down switch is released.
https://www.startekinfo.com/StarTek/...56/073-165.pdf
https://www.startekinfo.com/StarTek/...ine_560SEC.htm

At the top of the W126 forum page stickies there is link to service manuals.
07-06-2019 03:21 PM
lesguy Thanks H.D. I appreciate your knowledge sharing and guidance. I’m learning from it. Question: is my full throttle no upshift from 2-3 possibly related to my fuel system? Or is that most likely a coincidence? Doesn’t concern me excessively because I don’t redline this engine as a matter of routine. But still, one likes to have their drivetrain in top order.
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