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 > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 08-19-2014, 12:45 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
606 erratic idle

I just completed a timing chain replacement with a new tensioner. Everything lined up at TDC and I'm sure I didn't miss a tooth on the cam. At the same time, I replaced all six injectors with reman Bosch units ( I still have the old ones with Bosio nozzles but well worn at 120K on them.) The injectors nail worse than the previous ones, despite me bleeding the lines several times yesterday and today.

After getting everything buttoned up, primed and driven briefly, the car has now developed the infamous erratic low idle problem. I've searched the forum archives but can't find anything related to the w124 1995 606 engine on this subject.

When I first got the car 6 years ago, I replaced the ELR module behind the battery to solve an erratic idle problem. The ELR unit on the back of the IP also got changed out. At the same time, all the vacuum hoses were changed; an EGR bypass was performed with a bb and a copper freeze plug in the EGR tube attached the exhaust manifold, so there is no coke in the intake manifold causing any restrictions that could cause surging. I pulled the ELR module behind the battery and cleaned the contacts, then reinstalled it; no change in the symptoms afterwards.

The erratic idle problem seems to only rear its head after I start the car and blip the throttle. When I shut off the engine and restart it, the idle evens out again. I disconnected the two pin connector at the top of the ELR module in the IP and it drops to an even 500RPM; upon reattachment,the RPM jumps back up to 650-700ish then starts loping. There is consistent light grey smoke coming from the tailpipe, suggesting an IP timing problem.

Any suggestions appreciated, I'm at my wits end.


Last edited by clickclak; 08-19-2014 at 03:13 PM.
Reply With Quote
  #2  
Old 08-19-2014, 01:08 PM
Registered User
 
Join Date: May 2009
Location: The slums of Beverly Hills
Posts: 8,065
Any air bubbles in the clear fuel lines coming off the fuel filter mount?
__________________
CENSORED due to not family friendly words
Reply With Quote
  #3  
Old 08-19-2014, 01:32 PM
winmutt's Avatar
85 300D 4spd+tow+h4
 
Join Date: Apr 2006
Location: Atl Gawga
Posts: 9,346
Try adjusting timing with engine running and see if it gets better? Might not have missed a tooth on the cam but maybe on the IP? My bet is on the remans... Did you check for leaks? Cracked injectors tried to isolate?
__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42
Reply With Quote
  #4  
Old 08-19-2014, 03:03 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Quote:
Originally Posted by tjts1 View Post
Any air bubbles in the clear fuel lines coming off the fuel filter mount?
Hmm, didn't check those. I'll do that shortly. I did replace them 2 years ago but they could be cracked again due to heat.
Reply With Quote
  #5  
Old 08-19-2014, 03:05 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Quote:
Originally Posted by winmutt View Post
Try adjusting timing with engine running and see if it gets better? Might not have missed a tooth on the cam but maybe on the IP? My bet is on the remans... Did you check for leaks? Cracked injectors tried to isolate?
I don't know how to adjust timing on the IP, guess I'll have to check the FSM for that. I did check the for leaks on the injectors and attempted to isolate but found none so far, I'll check again.
Reply With Quote
  #6  
Old 08-19-2014, 03:11 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Update:

I just got back from errands and performed an italian tune up. Freeway speed on the interstate (70-80ish), followed by in town stop and go driving. The injectors have quieted down a lot.

The erratic idle goes away after I get the speed up, and it stays level after coming to a stop for the most part. But the moment I come to a stop and put it in park or neutral, say to go in to get the mail, leaving the engine running (doors locked of course), the loping comes back. When I shift to drive and go again then come to another stop light/sign, it sometimes stays level, other times it lopes a little then evens out.
Reply With Quote
  #7  
Old 08-19-2014, 03:20 PM
jake12tech's Avatar
Registered User
 
Join Date: Nov 2011
Location: Philadelphia, PA
Posts: 2,878
After injector replacement it needs a hard run to settle things down.

Adjust the IP timing after checking the manual from the procedure and we'll go from there.
Reply With Quote
  #8  
Old 08-19-2014, 03:40 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Quote:
Originally Posted by jake12tech View Post
After injector replacement it needs a hard run to settle things down.

Adjust the IP timing after checking the manual from the procedure and we'll go from there.
Thanks, I figured it had to be something related to the IP. I just checked all the clear lines coming from the filter housing to the pump; no sign of bubbles or cracks, nothing at the injectors. I just started it again after letting it sit for 20 minutes; the rpms came up level, but the moment I pulled the throttle lever and blipped it, the loping came back.
Reply With Quote
  #9  
Old 08-19-2014, 04:25 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Well, I checked the manual for the IP timing procedure and it involves getting several MB only electrical connectors, a digital meter and following the RIV method. Having never done this before, I performed a search here but came up with only hits on older 616 and 617 engines. Are there any references someone could point to that give the A-Z on how to set IP timing on a 606?
Reply With Quote
  #10  
Old 08-19-2014, 04:35 PM
Registered User
 
Join Date: Nov 2010
Location: TX
Posts: 3,978
you dont need any fancy connectors, all you need to do is to remove the locking pin plug from the injection pump governor housing, rotate the engine to 15 ATDC and look for the slot in the hole, it should be perfectly in the middle of it. If its not then you can rotate the injection pump to align it back.

My car once developed this loping issue which was resolved by fresh O rings on the clear pipes on the IP.
__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)
Reply With Quote
  #11  
Old 08-19-2014, 04:35 PM
Registered User
 
Join Date: Feb 2004
Location: Walnut Creek, CA & 1,150 miles S of Key West
Posts: 4,874
Are you certain you have the vacuum lines at the crossover and IM reconnected properly, and that there are no leaks?
__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)
Reply With Quote
  #12  
Old 08-19-2014, 04:36 PM
jake12tech's Avatar
Registered User
 
Join Date: Nov 2011
Location: Philadelphia, PA
Posts: 2,878
I'm a bit confused here. What year 606 is this? NA or Turbo?

The 97/99 pumps aren't electronic. They are mechanical pumps WITH electronic control. 97 and up diesels are drive-by-wire systems.

List in your signature what year and model MB this is for future reference.
Reply With Quote
  #13  
Old 08-19-2014, 04:38 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Quote:
Originally Posted by jake12tech View Post
I'm a bit confused here. What year 606 is this? NA or Turbo?

The 97/99 pumps aren't electronic. They are mechanical pumps WITH electronic control. 97 and up diesels are drive-by-wire systems.

List in your signature what year and model MB this is for future reference.
Yes I understand that. Its a 1995 E300D NA 606.910. My W124 FSM CD shows several subprocedures and I'm only repeating what it showed me.
Reply With Quote
  #14  
Old 08-19-2014, 04:42 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Quote:
Originally Posted by TMAllison View Post
Are you certain you have the vacuum lines at the crossover and IM reconnected properly, and that there are no leaks?
Yes. I took several pictures and double checked them. As for leaks, not 100% sure, I replaced all the vacuum tubing six years ago. I'll have to visually inspect again, it could be a bad piece of tubing.
Reply With Quote
  #15  
Old 08-19-2014, 04:44 PM
Registered User
 
Join Date: Nov 2006
Location: Dallas, TX
Posts: 60
Quote:
Originally Posted by Zulfiqar View Post
you dont need any fancy connectors, all you need to do is to remove the locking pin plug from the injection pump governor housing, rotate the engine to 15 ATDC and look for the slot in the hole, it should be perfectly in the middle of it. If its not then you can rotate the injection pump to align it back.

My car once developed this loping issue which was resolved by fresh O rings on the clear pipes on the IP.
Thanks, I'll check. The FSM seems to overcomplicate the issue.

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 03:03 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page