Terrible gas mileage/ performance - BMW Forum - BimmerWerkz.com
1,6,7,8 - Series and Mini Cooper General Chat related to models that do not fit into particular categories above. Please try to put your discussion in more appropriate sections. This section does cover the 1 Series, MINI Cooper and 8-Series vehicles: BMW 830i, BMW 840Ci, BMW 850i, BMW 850Ci, BMW 850CSi, M8, Alpina B12, BMW CS Concept and others.

 
LinkBack Thread Tools Display Modes
#1 (permalink) Old 04-05-2006, 01:14 PM
n00b
 
Join Date: Oct 2005
Posts: 37
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
kc740i is on a distinguished road
(Thread Starter)
Terrible gas mileage/ performance

1995 740i e38 ((109000 miles)) w/ k&N filter (only mod)


The car's performance has slowly been declining since i bought it about 7 months ago.


****OIL LEAK****
The car has an oil leak on the left side of the engine. When i drive on the highway a tiny bit of smoke and a very foul oil odor comes out of the engine bay. I have had the valve cover gaskets replaced about a month ago but there is still a leak somewhere. I am guessing it is leaking onto the exhaust manifold and that is causing the smoke but im not sure. When i turn the car on, i occasionally get white smoke comming out of the exhaust for about 5 seconds.


****Poor gas mileage and acceleration****

I am getting an average of 12 to 13 mpg including highway driving and i know this is definately NOT what this car is supposed to be getting. When i turn the car on, i can sometimes smell a very rich gas smell comming from the exhaust. The car does not accelerate as well as it used to and hesitates sometimes. Oxygen sensors or possibly more than that?

Is it possible that the oil leak has fouled out my spark plugs? I had them replaced about a month ago, but dunno if thats causing the poor performance.


Any suggestions would be appreciated
kc740i is offline  
Sponsored Links
Advertisement
 
#2 (permalink) Old 04-06-2006, 02:07 AM
5th Gear Member
 
325isBaby's Avatar
 
Join Date: Jul 2004
Location: Spokane, WA
Posts: 1,003
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
325isBaby is on a distinguished road
Send a message via MSN to 325isBaby
I would deffinatly start by checking the spark plugs, if you are smelling gas and you had an oil leak it could have deffinatly fouled your plugs...If you have fouled plugs this could affect your performance...Start there and work your way up. Good luck

http://www.myspace.com/330xigirl
Come see me at MySpace
325isBaby is offline  
#3 (permalink) Old 04-06-2006, 04:26 AM
n00b
 
Kyytsis's Avatar
 
Join Date: Mar 2006
Posts: 29
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Kyytsis is on a distinguished road
Have you had the fault codes read? Your local dealer has the equipment to check if there is something recorded in the cars computer. I'd not be amazed if you would find that some lambda-sensor is broken, that would partly explain the bad fuel economy.

Check all gaskets to see where the oil is pouring from. I know by expriance that the smell isn't a delight.. Everytime some one enters the car it's the first comment.

Regards,

Ville
Kyytsis is offline  
#4 (permalink) Old 04-19-2006, 03:17 PM
n00b
 
Join Date: Feb 2006
Location: Cleveland, OH
Posts: 19
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Othniel13 is on a distinguished road
Saw this - might help

I am doing some prepurchase research on a 740iL and literially just came to this forum from another that talked about a problem with idenitical symptoms. Check it out.

http://www.automotiveforums.com/vbul...d.php?t=550110

Could explain the left side oil leak, smoke, poor performance, etc.

Hope it helps!
Othniel13 is offline  
Sponsored Links
Advertisement
 
Reply

  BMW Forum - BimmerWerkz.com > BMW Model Specific Forums > 1,6,7,8 - Series and Mini Cooper


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
735IL Gas mileage dlinco 1,6,7,8 - Series and Mini Cooper 3 04-15-2006 08:20 AM
10% drop in gas mileage E46 - Why? SteveC 3-Series (E46, E90) 2 02-15-2006 09:13 PM
bmw e28 528e gas mileage 3serbmdubya 5-Series (E12,E28, E34, E39, E60) 7 01-19-2006 07:44 PM
Improve Gas Mileage & Performance 2000BMW323i 3-Series (E46, E90) 1 03-11-2005 10:36 PM
Performance chip appollo 3-Series (E36) 11 12-20-2003 01:17 PM

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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome