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 08-20-2010, 10:19 PM
Registered User
 
Join Date: Aug 2010
Posts: 6
240d misfire at idle

hi all,

1983 eurospec 240d. 113k miles. auto. When i got the car, it would start right up but stall without being given throttle. Idled really low and misfired.

Thus far I have changed the hand primer pump to the new bosch style (old one was leaking), changed the idle on the back of the injection pump to bring it to an acceptable range, adjusted the valves, changed out both fuel filters.

After all of the above, the car would start right up without stalling out. However, still had a rough idle with random misfire (but better than before). When in gear and stationary, the rough idle and misfire almost disappear. When driving around at speed, the misfire is nowhere to be found.

I'm at a loss at to what to try next, ideas? Thanks

Reply With Quote
  #2  
Old 08-20-2010, 10:33 PM
79Mercy's Avatar
Registered User
 
Join Date: Mar 2008
Location: Florida
Posts: 4,131
Cold or hot, or both?

Make sure that your not getting air in the fuel lines.

If its not air its most likely the fuel injectors, pull them out and have a diesel injection shop check and rebuild them if needed.
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
Reply With Quote
  #3  
Old 08-20-2010, 10:44 PM
Registered User
 
Join Date: Aug 2010
Posts: 6
both hot and cold, maybe a bit more when it's cold.


next step will be to replace the supply lines. the ones from the primer pump to the screw on fuel filter and from that filter to the IP. can those lines be bought at any auto parts store?

If that doesn't work i have another friend with a 300d and i'll try swapping in his injectors to see if that solves the problem.

any other ideas? thanks!
Reply With Quote
  #4  
Old 08-20-2010, 10:49 PM
Registered User
 
Join Date: Aug 2010
Posts: 6
btw there is a bubble of air in the clear filter, i'm assuming that's normal? no little bubbles fizzing or anything though.
Reply With Quote
  #5  
Old 08-20-2010, 11:21 PM
79Mercy's Avatar
Registered User
 
Join Date: Mar 2008
Location: Florida
Posts: 4,131
1 large bubble is fine in the filter.

No need to replace the hard plasitc lines unless they are broke.

Replace the rubber fuel line with 5/16 fuel rated hose.
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
Reply With Quote
  #6  
Old 08-21-2010, 12:18 AM
whunter's Avatar
Moderator
 
Join Date: Dec 2003
Location: Metro Detroit, Michigan
Posts: 17,416
Hmmm

Answer

Valve adjustment OM615, 616, 617 FYI.
http://www.peachparts.com/shopforum/showthread.php?t=107729

* Air entering the fuel system/contaminated fuel, partially plugged filters.
Fuel Delivery:
http://www.peachparts.com/shopforum/showthread.php?t=142399

* Diesel Injector issue.
Injector + Heat shield + Nozzle, Prechamber + Collar and Nailing. LINK THREAD
http://www.peachparts.com/shopforum/showthread.php?t=211750

* Diesel Injection Pump Timing issue.
Diesel Injection:
http://www.peachparts.com/shopforum/showthread.php?t=142405

* Fuel pressure relief valve, and/or the lift pump valvae are bad.

Fastlane: REBUILD KIT, DIESEL LIFT PUMP/FUEL PUMP, DOES NOT INCLUDE THE LARGE PLUNGER SPRING OR LARGE PLUNGER COVER SEAL RING, APPLICATION: OM616.912, OM617, 910, 912, 950, 951, 952
http://catalog.peachparts.com/item.wws?sku=0000900210
pictures on install are here.
OM617.951 and .952 Lift pump Repair kit W126.120 300SD W123.133 300D
http://www.peachparts.com/shopforum/showthread.php?p=1461282

Fuel injection pump starvation with good a good lift pump
http://www.peachparts.com/shopforum/showthread.php?p=2133911

Fuel pressure relief valve adjustment
http://www.peachparts.com/shopforum/showthread.php?t=234609

lift pump test
http://www.peachparts.com/shopforum/showthread.php?t=277893

fuel pressure
http://www.peachparts.com/shopforum/showthread.php?p=2156755

Last edited by whunter; 08-25-2010 at 01:58 AM.
Reply With Quote
  #7  
Old 08-21-2010, 02:06 AM
gastropodus's Avatar
Mercedes Benz apprentice
 
Join Date: May 2010
Location: Portland, OR
Posts: 434
Have you checked compression? If you've got a low cylinder (typically #1) it will miss when cold and at idle, yet often be fine at road speed.

Kurt
__________________
- '79 240D - engine swap complete! Engine broken in! 28-31 mpg! Lovin' the ride!
- '86 190D (W201-126) - 2.5 NA engine, 5 speed, cloth interior, manual climate controls, 33-34 mpg (sold to forum member).
Reply With Quote
  #8  
Old 08-21-2010, 05:24 AM
t walgamuth's Avatar
dieselarchitect
 
Join Date: Apr 2005
Location: Lafayette Indiana
Posts: 38,613
Quote:
Originally Posted by gastropodus View Post
Have you checked compression? If you've got a low cylinder (typically #1) it will miss when cold and at idle, yet often be fine at road speed.

Kurt
This is a thought I was having.

I will make a slight different comment about what happens on the highway...

It may feel fine but if you are low on compression on a cylinder it will be making less power it is just not as noticable as at idle.
__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.
Reply With Quote
  #9  
Old 08-21-2010, 12:24 PM
Biodiesel300TD's Avatar
|3iodiesel300T|)
 
Join Date: Dec 2004
Location: Albany, OR
Posts: 4,845
I doubt that it is an air leak. Usually air leaks get worse when you try to drive, because you start pulling more air into the system. I'd start with a valve adjustment. You could have valves that are way out of adjustment. On these cars as the valve clearances get out of adjustment the clearances tighten up, which causes the valves to not close all the way which causes compression to go down. I'd adjust the valves and then run a couple cans of diesel purge through the fuel system and see what happens.

You can also loosen the hard lines ones at a time to each injector, with the engine running. The engine should run rougher when you crack open a line. If you find one that doesn't change the idle as much as the others or at all you've found the culprit cylinder. This points to injector or compression. But I'd do the valve adjustment and diesel purge first.

Also you should adjust the valves before you do a compression test due to the reason I stated above. Mis-adjusted valves with lower compression, and give you a false reading.
__________________
Andrew
'04 Jetta TDI Wagon
'82 300TD ~ Winnie ~ Sold
'77 300D ~ Sold
Reply With Quote
  #10  
Old 08-24-2010, 10:36 PM
Registered User
 
Join Date: Aug 2010
Posts: 6
Quote:
Originally Posted by gastropodus View Post
Have you checked compression? If you've got a low cylinder (typically #1) it will miss when cold and at idle, yet often be fine at road speed.

Kurt
went out and bought the harbor freight tools diesel compression tester tonight. with all 4 glow plugs removed and the engine cold, tested compression through the glow plug holes. all 4 cylinders read right around 450. from what i have read, new spec was 425ish? any ideas? at any rate the compression seems to not be the issue? so most likely an injector issue?
Reply With Quote
  #11  
Old 08-24-2010, 11:09 PM
Craig
Guest
 
Posts: n/a
I agree with adjusting that valves if they are due. Tight valves will cause a miss, both hot and cold.
Reply With Quote
  #12  
Old 08-25-2010, 07:44 AM
Registered User
 
Join Date: Nov 2008
Location: Annapolis, MD
Posts: 180
Living a similar problem on my '83 Euro 240d, manual. Misses a little when cold, but fine when warm. Haven't done valves yet, but believe this is most likely it. Previous owner said he did a valve adjust, but you can't do too many...

All new filters, lines look good.

Watching with interest.
__________________
05 E320 CDI
99 SL500
02 530i

82 240D SOLD
83 240D Euro 4spd SOLD
86 300D Euro Auto SOLD
Reply With Quote
  #13  
Old 03-02-2011, 02:35 PM
Registered User
 
Join Date: Mar 2011
Location: chester,s.c.
Posts: 4
hi-let me know out come please have a simular situation , hot/cold but great on hy,way
me thinks at idle injectors / i.p one has low pressure , higher rpm higher pressure , using
infared thermometer 2&5 not as hot as others got 2 new injecters on the way,bought 5 supposed to be cleaned , ugh. u never know , any body agree with my assumption
Reply With Quote
  #14  
Old 03-02-2011, 07:06 PM
Registered User
 
Join Date: Jun 2008
Posts: 78
Adjusting the valves has been recomended several times. Is there some reason you want to skip this simple and free repair. If the valves are out of adjustment, no amount of diagnostics will solve the problem. You might get lucky by replacing the injectors, or the timing chain, or the injection pump, ect. However you could go on throwing money and parts at the misfire, and never find the real source of the problem. Adjusting the valves was suggested by some of the more knowledgeable members of this site.
Reply With Quote
  #15  
Old 03-02-2011, 07:16 PM
mike-81-240d's Avatar
I like coffee
 
Join Date: Mar 2009
Location: Bellevue, WA
Posts: 872
When cold are you using the high idle control knob prior to starting?

__________________
1981 300TD 4 speed manual
Euro bumpers, zender valance and skirts, H&R springs, billy HD's, leveled sls, real AMG Pentas 16x8 et11, vdo boost/egt gauges intergrated into ash tray, eurolights, led 3rd brake light
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 05:30 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