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 12-29-2004, 04:00 PM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Engine bogs at 3000RPM under full throttle

Hey everybody,
My 86 300E bogs at 3000 rpm under full throttle. If I slowly accelerate it is fine, but if I floor it it bogs. I was thinking maybe OVP, or the fuel accumulator by the fuel pump. I just replaced the fuel pump this week. Died on the 101 north of LA. Any advice? Thanks,

Mike

Reply With Quote
  #2  
Old 12-30-2004, 01:17 AM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey guys,
tried clamping acumulator line going to fuel pump inlet, didn't seem to help. How do you know if OVP is bad?

Mike
Reply With Quote
  #3  
Old 12-30-2004, 02:42 AM
haasman's Avatar
Registered User
 
Join Date: Jun 2001
Location: San Francisco, CA
Posts: 3,097
Sounds like a load issue. Does it do it under hard acceleration from a standing start?

How old is the cap and rotor?

Haasman
__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)
Reply With Quote
  #4  
Old 12-30-2004, 07:30 PM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey Haasman,
If the car is in park and I floor it it bogs at around 3000rpm, while driving it just feels sluggish off the line, but also while driving, if I floor it it bogs. If I gently accelerate it's fine, but get on the gas and no good . Not a lot of fun. I have replaced spark plugs, spark plug wires, rotor, cap, coil, fuel filter, fuel pump. I have replaced all fluids besides oil with synthetic, including transmission. This has all been recent. I replaced all injectors 2 years ago, and the car sat up until 4 months ago.

Mike
Reply With Quote
  #5  
Old 12-31-2004, 12:18 AM
haasman's Avatar
Registered User
 
Join Date: Jun 2001
Location: San Francisco, CA
Posts: 3,097
Does the engine feel like it is missing or simply won't rev at 3,000 RPM?

When I got the 190e, it ran very poorly. A Mercedes tech friend suggested bleeding the injectors AT the fuel distributor while the engine was running at idle. I was a bit dubious but with a fire extinguisher close at hand and lots of rags I did it.

I was amazed at the amount of crud that came out. I did each line until there was no more crud. The old engine ran quite well right afterwards.

Haasman
__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)
Reply With Quote
  #6  
Old 12-31-2004, 02:50 AM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey Haasman,
The best description is it just bogs. It doesn't seem like it misses, just either not getting enough fuel, spark, or possibly the timing getting retarded from a malfunctioning OVP. How did you bleed the injectors with the engine running? Did you unscrew the line at the fuel distributor, or at the injector? How would the crud make it past the fuel filter? Could lack of fuel to individual cylinders cause problems. Would it be possible to bleed with the key in the on position but the car not running? Thanks for the help,

Mike
Reply With Quote
  #7  
Old 12-31-2004, 10:12 PM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey Haasman,
Some more info. I replaced the OVP today without any improvement. I also unplugged the kickdown switch. The car ran the same with it unplugged as it did with it plugged in. When accelerating hard it downshifted even with the kickdown switch disconnected. I'm really at a loss with this problem. When it down shifts, the rpm's go up but the car doesn't accelerate. If the car is in park and you floor it, it hesitates between 3000-4000 rpm. If you slowly rev it the rpm's go above 5000 no problem. It just seems to be a problem when the accelerator is pushed down too fast. Thanks for the help,

Mike
Reply With Quote
  #8  
Old 01-01-2005, 12:20 AM
haasman's Avatar
Registered User
 
Join Date: Jun 2001
Location: San Francisco, CA
Posts: 3,097
Mike

You are asking great questions ... first the fuel lines are bled at the fuel distributor so you will need to take the air cleaner off. Yes, while the engine is running so only crack the retaining nut holding the line in so that the crud dribbles out. Do it several times. Have lots of rags handy and BE CAREFUL.

You should measure your fuel pressure. Pull the distributor cap and look for signs of arching. Did you use a Mercedes spec rotor and cap?

Haasman
__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)
Reply With Quote
  #9  
Old 01-01-2005, 04:32 PM
Registered User
 
Join Date: Aug 2001
Location: Evansville, Indiana
Posts: 8,150
Fuel delivery problem. Check the air flow meter venturi (probably dirty) -- if the air flow flap sticks, it will go way lean and stumble.

you should also replace the fuel filter and verify that the accumulator is good and that the pumps are working properly.

Bad O2 sensor isn't an impossiblity, either.

Peter
__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
Reply With Quote
  #10  
Old 01-02-2005, 02:09 AM
wbain5280's Avatar
Registered User
 
Join Date: May 2001
Location: Northern Va.
Posts: 3,386
Check the coil wire where it clippes on, especially under the dist. cover. My 300SE's coil wire was burned at that clip on point. When I sealed up my front cover leak, I put some Locktite 5900 on the burned area. The car has been running well since.
__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
Reply With Quote
  #11  
Old 01-12-2005, 04:09 PM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey guys,
Thanks for the input.

Haasman, rotor is bosch, cap is another brand but looks good. How do you test fuel pressure? Is there any way to rent equipment? I bled the lines going to each injector, a little bit of rusty looking crud came out but not much. acceleration didn't improve much.

psfred, Where is the airflowmeter venturi? I recently replaced filter, and the pump. How do you check accumulator? I have also replaced the O2 sensor a couple of months ago.

wbain, The coil wire looks good at both the distributor and coil.

What role does the coolant temp sensor play with throttle response? Yesterday when the car was cold, and in park I could floor it and it would rev to redline without bogging. Once the car got above 80C, it goes back to the standard bogging between 3K to 4K. Also when the car is above 80C, if I rev the accelerator very slowly and smoothly it goes to redline fine. When driving the car it accelerates very sluggishly, and in the California hills, it is very sluggish also. Unfortunately the more gas you give it the more sluggish it feels. Thanks for the help.

Mike
Reply With Quote
  #12  
Old 01-12-2005, 04:25 PM
Registered User
 
Join Date: Jul 2004
Location: York, PA
Posts: 621
When cold the temp sensor tells the CIS-E to run rich. When at temp it leans up to normal mixture. Whatever that is set to. Have you checked you mixture yet? I have the same issue on my 190E. Just did the head gasket last weekend and it is still there. Ordered a new fuel filter, old one is only a year old, and new injectors for the 2.3 yesterday. I will put the injectors in after work and test it tomorrow. If it still is bad than at lunch I will do the filter again. I gutted my pre-cats when I did the head gasket as they had a white looking soot all over the top of them. So I banged em out thinking that may have been my issue. From what it sounds like you could have a bad or clogged Cat too. Mine feels like it is not getting enough fuel or air over 3/4 pedal, on a hill it is 1/2 pedal. Getting on the highway is quite a challange to keep the pedal under 1/2 so I can actually accelerate. I am crossing my fingers here. If all the crap I just did does not help then off comes the damn Cat because that is all that is left for me. Have new Bosch everything in that damn car. Also found that the Bosch Spark Plug wire set I ordered from *********************** tested out to 1.6K ohms from plug to plug. They are supposed ot be 1 KOhm. 600 Ohm diference is off somewhat. I bought new plug connectors as well, they tested at 1.2K without any wire on them at all. Looked at the very first one I bought from the Dealer and that one tested perfect to 1K. Wierd hoe there is such a diference, the dealer must get the better Bosch stuff. I will post tomorrow with what I get out of mine. Also have you run any injector cleaner through? After sitting maybe you have a stickie injector or two.
__________________
~Jamie
_________________
2003 Pewter C230K SC C1, C4, C5, C7, heated seats, CD Changer, and 6 Speed. ContiExtremes on the C7's.

1986 190E 2.3 Black, Auto, Mods to come soon.....
Reply With Quote
  #13  
Old 01-12-2005, 04:44 PM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey Jamie,
Thanks for the info. Maybe it is the cat, but why would it run different if hot or cold. If cat was bad wouldn't it run the same hot or cold? As far as cleaning injectors goes, I run lubromoly jectron and ventil sauber once a month. Let me know how it works out,

Mike
Reply With Quote
  #14  
Old 01-12-2005, 04:47 PM
Registered User
 
Join Date: Oct 2004
Location: San Diego, Ca
Posts: 24
Hey jamie,
Forgot to mention that mine does the same as yours in terms of accelerating. Kinda sucks when you can't count on acceleration.

Mike
Reply With Quote
  #15  
Old 01-12-2005, 07:25 PM
Registered User
 
Join Date: Sep 2002
Location: Kingsport, TN
Posts: 375
When I replaced the fuel pumps and everything around it on my 420, the engine would not go above 3000 rpms. Turned out I had routed one of those hoses the wrong way and it had a kink that didn't let enough fuel through.
After re-routing and the use of some ties, voila, no more problem. Look at your fuel pump hoses.
Attached Thumbnails
Engine bogs at 3000RPM under full throttle-plastic-clip-installed2.jpg  

__________________
Reinhard Kreutzer
1987 420 SEL (126)
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 08:04 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