e34 540i 1994 fuel consumption gauge.. - BMW Forum - BimmerWerkz.com
5-Series (E12,E28, E34, E39, E60) Chat relating to the BMW 5-Series of all generations. Specific models include: BMW 518, BMW 520, BMW 520i, BMW 530i, BMW 528i, BMW 530i, BMW 518i, BMW 524d, BMW 525i, BMW 525e, BMW 528e, BMW 540i, BMW 535i, BMW 520d, BMW 525td, BMW 525d, BMW 530d, BMW 525i/xi, BMW 530i/xi. (BMW 5-Series Forum)

 
LinkBack Thread Tools Display Modes
#1 (permalink) Old 02-01-2009, 07:04 AM
n00b
 
longdom's Avatar
 
Join Date: Jan 2009
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
longdom is on a distinguished road
(Thread Starter)
e34 540i 1994 fuel consumption gauge..

hi to all,
does anyone know why my fuel consumption gauge, the half moon shaped one under tacho, all of a sudden has gone crazy???

when car is off, its at 0
when driving it moves around, but doesnt really look like its stable.
when im idling, its at maximum fuel consumption, actually so high, i cant see the needle..and have noticed on obc, that my consumption levels have risen from 11.5-12.6 average, to 15 and climbing still...(thats lt/100km).

anyone have any ideas?????
thanks again........
longdom is offline  
Sponsored Links
Advertisement
 
#2 (permalink) Old 02-02-2009, 01:03 AM
Millions of them.
 
Torque's Avatar
 
Join Date: Dec 2003
Location: USA
Posts: 14,878
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute
That's how it works.

1. When it's off, you're using no fuel ...
2. It's by no means accurate; it's pretty much dependent on throttle inputs to get it's estimation.
3. Think about it. You're idling, therefore fuel is being used, yet you're getting no movement. You could use up a 1000 liters and not move at all, so yes, the consumption average will climb on the OBC, just like it does mathematically if you were to calculate it yourself.
4. You're being paranoid.

Torque is offline  
#3 (permalink) Old 02-02-2009, 03:04 AM
n00b
 
longdom's Avatar
 
Join Date: Jan 2009
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
longdom is on a distinguished road
(Thread Starter)
ok..so why was it different for the first month that i drove the car????
and now its been a week, that its like this???

the fuel gauge was always on 0 when idling, and would move with acceleration, obviously, and consumption was 11-12.8lt/100km, i have been following it, now all is different...explain that...
longdom is offline  
#4 (permalink) Old 02-02-2009, 03:05 AM
n00b
 
longdom's Avatar
 
Join Date: Jan 2009
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
longdom is on a distinguished road
(Thread Starter)
did you read my thread?? by the way...
longdom is offline  
#5 (permalink) Old 02-02-2009, 11:47 AM
Millions of them.
 
Torque's Avatar
 
Join Date: Dec 2003
Location: USA
Posts: 14,878
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute Torque has a reputation beyond repute
Quote:
Originally Posted by longdom View Post
ok..so why was it different for the first month that i drove the car????
and now its been a week, that its like this???

the fuel gauge was always on 0 when idling, and would move with acceleration, obviously, and consumption was 11-12.8lt/100km, i have been following it, now all is different...explain that...
Then it was broken before. The consumption can't be 0 l/100km if the engine is running and you're not moving. Your consumption is actually infinite, that's why you can't see the needle.

Torque is offline  
#6 (permalink) Old 02-02-2009, 01:11 PM
Neutral Member
 
Join Date: Aug 2008
Posts: 66
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
MADDOUG is on a distinguished road
If it does not look stable,it should sweep back and forth slowly on gentle throttle and nip back sharpish to near zero when cars given some,then check under the drivers dash knee high panel,on my 94 tds the sensor that works it lives there,mine has a vacuum connection to it (diesel turbo) plus the multiplug,yours may have a vacuum connection and maybe dodgy engine vacuum or leaking pipe is confusing it.As for tickover it goes off and no throttle at speed in my autobox equipped car it will show about 20mpg at 80mph simply because the box is in 5th gear lock up mode,other gears coasting the engine drops to tickover and it goes off with needle dropping back past zero to its home position.Driving at constant speed the needle should stay still,slight on or off throttle will get it to move either way,and a boot full gets it to move quickly to 15/20mpg,yours may well move quicker as yours is not capable of near 50mpg.
MADDOUG is offline  
#7 (permalink) Old 02-15-2009, 09:35 AM
n00b
 
longdom's Avatar
 
Join Date: Jan 2009
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
longdom is on a distinguished road
(Thread Starter)
problem still not resolved...
i will look under dash and let you know what i find.
but idling, i notice on obc that consumption reaches and passes 40lt/100km, and gauge is higher than maximum, it used to sit on 0 when idling, then i must of touched something under dash, when i tried to get to brake light switch, since then its gone crazy..

so you say under dash, can you describe exactly what im looking for, cause i think that could be the problem.
thanks..
longdom is offline  
#8 (permalink) Old 02-15-2009, 09:52 AM
Neutral Member
 
Join Date: Aug 2008
Posts: 66
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
MADDOUG is on a distinguished road
When you take the panel out that fits in front of your knees,the padded one,on the back should be a small box about half the size of a cigarette packet,this has a multi plug that has around about 7/8 thin wires going in it,and the vacuum pipe goes into one side of it.When I first see this on my car I thought it was the buzzer or gong for the 'lights on alarm' and then I clocked the vacuum pipe and the multiplug,the multi plug wiring is traceable back to the throttle pedal potentiometer so if yours is not on the back of the panel then follow the wiring from the throttle pedal to find it.
MADDOUG is offline  
#9 (permalink) Old 02-15-2009, 12:31 PM
n00b
 
MeanM50's Avatar
 
Join Date: Apr 2008
Location: PDX
Posts: 24
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
MeanM50 is on a distinguished road
If your ECO gauge is not 'working right', I would suspect that the gauge is correct and there is a problem elsewhere on the car. It's true that these cars figure MPG as an average....so when you are idling, you SHOULD register a 0 MPG....because you are using fuel but not accumulating milage. This is why the OBC MPG and consumption figures are incorrect.

If anything, I would say that the ECO gauge was incorrect for the first month, and is now correct and functioning properly.

MeanM50 is offline  
#10 (permalink) Old 02-15-2009, 08:01 PM
1st Gear Member
 
Join Date: Feb 2009
Location: Las Vegas
Posts: 273
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
coolvegase34 is an unknown quantity at this point
I have a quick suggestion. Fill up your tank with gas. Reset your trip odometer. Drive until you have used 3/4 of a tank of gas. Fill it up. See how many miles you drove via your trip odometer. Divide the miles by the gallons used and that is your gas mileage. This is how we did it before we had fancy computers. These cars get horrible gas mileage, I don't care what year or model it is. That floating mpg indicator is so inaccurate. They just put it there so it looks cool. But, guess what? You don't by a bmw because you care about gas mileage. Drive it and enjoy. If you want 30mpg, buy a japanese econobox. That is what I drive when gas costs $4.55 per gallon. My Bmw sits in the garage.
coolvegase34 is offline  
#11 (permalink) Old 02-17-2009, 06:59 PM
n00b
 
MeanM50's Avatar
 
Join Date: Apr 2008
Location: PDX
Posts: 24
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
MeanM50 is on a distinguished road
Quote:
Originally Posted by coolvegase34 View Post
These cars get horrible gas mileage, I don't care what year or model it is.
A 2.5 liter six that gets 25MPG? Yeah....that's horrible. Just as horrible as my wife's Honda Accord.....only my BMW has more power, is quieter, and rides nicer.

MeanM50 is offline  
#12 (permalink) Old 02-17-2009, 07:41 PM
1st Gear Member
 
Join Date: Feb 2009
Posts: 110
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
JesterMX6 is on a distinguished road
my current m50 nor my mom's that she had for years never did better than 20mpg in town

BMW 535i - A Fillet on Wheels, Rare but Well Done

88 Mazda MX-6 GT :: 78 Suzuki GS550E :: 88 Mazda 323 GTX :: 90 BMW 535i/5 :: 87 Mazda MX-7 GTII
JesterMX6 is offline  
#13 (permalink) Old 02-23-2009, 01:41 AM
n00b
 
longdom's Avatar
 
Join Date: Jan 2009
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
longdom is on a distinguished road
(Thread Starter)
well looked where you told me to look, MADDOUG, all i have after i remove the panel is the gong, with 2 sets of wires coming out of it, and the a/c tube that goes to feet...
im talking about drivers side, right hand drive bmw...nothing else behind panel thats knee height.
will look on throttle pedal next, to see if i can locate any wires...will let you know..
longdom is offline  
#14 (permalink) Old 02-23-2009, 05:26 AM
n00b
 
longdom's Avatar
 
Join Date: Jan 2009
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
longdom is on a distinguished road
(Thread Starter)
found nothing, and no wires from throttle..
i give up..
anyone have photos or diagrams, as to where i can check if this gauge is working?
i have pulled the damn car apart 3 times and to no avail...
longdom is offline  
Sponsored Links
Advertisement
 
Reply

  BMW Forum - BimmerWerkz.com > BMW Model Specific Forums > 5-Series (E12,E28, E34, E39, E60)


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
new owner of a nice e34 540i 1994 V8 longdom New Members Check In 3 03-18-2011 02:49 PM
1994 BMW 540i e34 vs. 1992 Mercedes 400E ThomasD3 5-Series (E12,E28, E34, E39, E60) 11 10-19-2010 04:41 PM
318' E36 Fuel Gauge And Temp Gauge Problems Help!! mrfunk 3-Series (E36) 7 04-28-2010 06:22 PM
Need Help 1994 E34 540i.... longdom 5-Series (E12,E28, E34, E39, E60) 27 11-08-2009 08:06 PM
Fuel consumption sp0rky 5-Series (E12,E28, E34, E39, E60) 0 10-12-2003 02:00 AM

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