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 02-07-2010, 04:41 PM
Texholdem
 
Join Date: Mar 2007
Location: Dallas
Posts: 756
What should that open-ended vacuum line be connected to ?

Hi,

I removed the air filter housing (1990 300CE) and found an open-ended vacuum line, at the other end it is connected to some part (with the blue dot, what is it called?), which is in turn connected to the fuel distributor.

What should the open end be connected to. Is it something which causes my engine run too rich?



__________________
1996 E320 since 1/16/08, 171K miles as of Feb 2011

---------------------------------------------------------
1989 300CE - R.I.P. Dec 29 2007
Other MBs (sold): 1992 300E-24 - 1979 350SLC - 1984 230E - 1990 300CE
Reply With Quote
  #2  
Old 02-07-2010, 07:13 PM
Registered User
 
Join Date: Jan 2008
Location: Melbourne Australia
Posts: 844
That item with the blue dot is the fuel pressure regulator. Inside it there is a "rubber" diaphragm that helps in the regulators operation. If the diaphragm is damaged then fuel can escape out that line you are questioning. This line is not a vacuum line, it is a fuel escape line. It plugs into the rubber hose which runs between the valve cover and the air cleaner cover - item 1 in the image below. Note that the image shows the rear of the interconnecting hose. If you check the other side you will find an inlet into which your mysterious hose fits into.

Item 1 in this image.

Reply With Quote
  #3  
Old 02-07-2010, 07:20 PM
PanzerSD's Avatar
Schießenstern
 
Join Date: Jan 2006
Location: Saskatchewan Canada
Posts: 2,351
I wondered the same thing, but sort of came to that conclusion on my own.
Whilt at this topic, Lets say there was a fault in the regulator..what would some symptoms of a bad fuel pressure regulator be?
__________________
RIP: 80 300SD
RIP: 79 450SEL
2002 E430 4matic (212,000km)
2002 ML500 'sport'

____________________________
FACEBOOK:
PANZER450
Reply With Quote
  #4  
Old 02-07-2010, 08:50 PM
Texholdem
 
Join Date: Mar 2007
Location: Dallas
Posts: 756
Quote:
Originally Posted by Ivanerrol View Post
That item with the blue dot is the fuel pressure regulator. Inside it there is a "rubber" diaphragm that helps in the regulators operation. If the diaphragm is damaged then fuel can escape out that line you are questioning. This line is not a vacuum line, it is a fuel escape line. It plugs into the rubber hose which runs between the valve cover and the air cleaner cover - item 1 in the image below. Note that the image shows the rear of the interconnecting hose. If you check the other side you will find an inlet into which your mysterious hose fits into.

Item 1 in this image.

Thanks, so the fuel escape line runs into item # 2 in your pic?
__________________
1996 E320 since 1/16/08, 171K miles as of Feb 2011

---------------------------------------------------------
1989 300CE - R.I.P. Dec 29 2007
Other MBs (sold): 1992 300E-24 - 1979 350SLC - 1984 230E - 1990 300CE
Reply With Quote
  #5  
Old 02-07-2010, 10:34 PM
Registered User
 
Join Date: Jan 2008
Location: Melbourne Australia
Posts: 844
Quote:
Originally Posted by Texholdem View Post
Thanks, so the fuel escape line runs into item # 2 in your pic?
No. Goes into item 1. This is an image of the rear side. On the front side you will find a small slot to plug your line into.
Reply With Quote
  #6  
Old 02-07-2010, 11:57 PM
Texholdem
 
Join Date: Mar 2007
Location: Dallas
Posts: 756
Quote:
Originally Posted by Ivanerrol View Post
No. Goes into item 1. This is an image of the rear side. On the front side you will find a small slot to plug your line into.
Yes, I found the hole and plugged the line into that. Thanks a lot.
__________________
1996 E320 since 1/16/08, 171K miles as of Feb 2011

---------------------------------------------------------
1989 300CE - R.I.P. Dec 29 2007
Other MBs (sold): 1992 300E-24 - 1979 350SLC - 1984 230E - 1990 300CE
Reply With Quote
  #7  
Old 02-08-2010, 05:17 AM
Registered User
 
Join Date: Jan 2008
Location: Melbourne Australia
Posts: 844
Quote:
Originally Posted by PanzerSD View Post
I wondered the same thing, but sort of came to that conclusion on my own.
Whilst at this topic, Lets say there was a fault in the regulator..what would some symptoms of a bad fuel pressure regulator be?

This is a pain to diagnose without the proper diagnostic equipment. The symptoms of a faulty fuel pump regulator include rough running or bad idle. You generally start to chase all the other components in the KE system for the fault condition.

If you see fuel in that escape hose then you know it's knackered.

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 08:15 PM.


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