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 12-12-2006, 09:26 PM
Registered User
 
Join Date: Jun 2003
Location: Brick, NJ USA
Posts: 17
Poor Fuel Economy .. 99 E300

Well, I guess the title says it all.

99E300, 156K on her .. and the fuel economy is almost always 25 mpg, all highway. My assuption was she'd get at least low 30's highway.
Yes, the car is new to me (though I had an 83 300SD and am my second TDI).
Starts well - regardless of temperature, the power is always on tap. The MAF was replaced - had a CEL for it, a few other odds and ends (air filter, etc. Basic maintenance stuff) A lot of smoke during strong accelleration. My first thought is she's dumping excess fuel into the cylinders, but how?
Where shall I look first?

Reply With Quote
  #2  
Old 12-12-2006, 09:36 PM
POS's Avatar
POS POS is offline
Registered User
 
Join Date: May 2004
Location: Houston, Texas
Posts: 2,506
First look at a new fuel filter - that'll have a lot to do with bad mpg. Tire pressure while you're at it.

Smoke during acceleration (black smoke) is okay - A LOT of smoke could mean air filter (did you replace it?), another issue that I'm not aware of, or it's just the way your particular car is.
__________________
- Brian


1989 500SEL Euro
1966 250SE Cabriolet
1958 BMW Isetta 600
Reply With Quote
  #3  
Old 12-12-2006, 09:37 PM
Scott98's Avatar
Registered User
 
Join Date: Aug 2003
Location: Weston, FL
Posts: 1,254
I had the exact same problem on my 98 E300 as you and here is how I improved my economy from 28mpg to 34mpg:

http://www.peachparts.com/shopforum/showthread.php?t=145076&highlight=fuel

Good luck.

Scott
__________________
Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)
Reply With Quote
  #4  
Old 12-12-2006, 10:10 PM
Registered User
 
Join Date: Dec 2004
Location: Nashua, NH
Posts: 3,956
Now that I have had my '98 for two full years I can say that fuel economy always suffers in the cold weather. Check the air and fuel filters but don't be surprised if in spring you start to see economy closer to 30 around town and 34 on the highway. I routinely see fluctuations on the order of 10-15% on MPG and it is always lower in the cold...probably a combination of winter blend fuel and lower effeciency of the engines in the cold weather.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz
Reply With Quote
Reply

Bookmarks


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 01:41 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, 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