Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 08-26-2011, 11:09 AM
just-n-time's Avatar
Registered User
 
Join Date: Feb 2006
Location: Louisiana266 Maloy Rd winnfield71483
Posts: 804
Cool X11 reading 90 420SEL

Ok I have not had a reading of 2&3 That has any movement when I put my digital meter on percent, IE the reading is a constant 50.2% to 50.3% from cold to hot or warmed up to operating temp. It had a check eng. lite so I put a new ox sender in and have no fluxuation in the test reading as normal. can some one direct me toward likely reasons? thanks.

Reply With Quote
  #2  
Old 08-29-2011, 08:35 AM
Moderator
 
Join Date: Mar 1999
Location: Tucker, Ga USA
Posts: 12,153
Is the car a California version? Blink pushbutton & red LED on the diagnostic connector?
__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator
Reply With Quote
  #3  
Old 08-29-2011, 05:35 PM
just-n-time's Avatar
Registered User
 
Join Date: Feb 2006
Location: Louisiana266 Maloy Rd winnfield71483
Posts: 804
California car not

Quote:
Originally Posted by mbdoc View Post
Is the car a California version? Blink pushbutton & red LED on the diagnostic connector?
no it is not ca. car. the Duty cycle reading that I have had in the past has always had a fluxuasion when I check it and set it around 49% bounces from that to 51% some times higher. but after this ox sensor, it is riveted to a fixed number. thanks memory
Reply With Quote
  #4  
Old 08-29-2011, 05:57 PM
LandYaghtLover's Avatar
Registered User
 
Join Date: Jun 2010
Location: Green Bay, WI
Posts: 1,341
Maybe the new sensor is not hooked up right? Unplug it an see if there is a change. Mine fluctuates greatly, but I read it just as voltage, then add then up and divide by two.
__________________
1991 560 SEL / 185k miles
1992 750il / 17k miles - project car
Reply With Quote
  #5  
Old 08-29-2011, 10:52 PM
Registered User
 
Join Date: Dec 2007
Location: NorCal
Posts: 1,332
I had this same problem with my 300E. The engine ECU failed in such a way that the car was always in "open loop", thus operating at a fixed duty cycle value all the time and never entering "closed loop".
__________________
http://i193.photobucket.com/albums/z...-RESIZED-1.jpg
1991 300E - 212K and rising fast...
Reply With Quote
  #6  
Old 09-02-2011, 09:04 AM
just-n-time's Avatar
Registered User
 
Join Date: Feb 2006
Location: Louisiana266 Maloy Rd winnfield71483
Posts: 804
Thumbs up duty cycle

Quote:
Originally Posted by JohnM. View Post
I had this same problem with my 300E. The engine ECU failed in such a way that the car was always in "open loop", thus operating at a fixed duty cycle value all the time and never entering "closed loop".
I suspect this to be a proublem with the ECU, though I was looking for more morral support. I thought Doc had this one but I am slow to respond to the MB forum with every thing else going on at the present time. I do thank you for the pennies, and I hope you are having good luck with your ride. Memory you know I just rememberd that after working on my wifes dd a 91 190E 2.6 I used her old ox sensor and put it in to the 420 could this be the trouble are they unit specific? the 420 had a cel and it stopped after replacing with other ox.could this be the reason for the open loop?


Last edited by just-n-time; 09-02-2011 at 09:51 AM.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 04:31 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page