Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club General Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 19th April 2010, 07:23   #1
rossocorsa
Posted a thing or two
 
None

Join Date: Feb 2010
Location: GRIMSBY
Posts: 1,243
Thanks: 0
Thanked 1 Time in 1 Post
Default fuel gauge slightly weird

is this normal? I park up with quarter plus in tank leave over night and then in the morning gauge has dropped and low fuel comes on, start driving and over the next 5 miles or so the gauge rises back up to where it was the night before!! I'm guessing that one of the tank sensors might be sinking overnight? As well question is which reading is correct.......
rossocorsa is offline   Reply With Quote
Old 19th April 2010, 08:03   #2
the monk
Avid contributor
 
Rover 75 1.8T

Join Date: Dec 2009
Location: sunderland
Posts: 100
Thanks: 0
Thanked 0 Times in 0 Posts
Default

I don't think it is normal. When I first start my car, the light does come on and takes about 10 seconds to go out and the guage to show how much fuel is in.
Could be the sender unit needs an early cup of coffee.
the monk is offline   Reply With Quote
Old 19th April 2010, 10:06   #3
amableson
Gets stuck in
 
amableson's Avatar
 
Ex Rover 75 owner

Join Date: Nov 2006
Location: Boston, Lincolnshire.
Posts: 553
Thanks: 0
Thanked 2 Times in 2 Posts
Default

When you get into the car before putting on the ignition push the trip reset button and the mileage and fuel level should read for a time.That should a least test it.
__________________
Regards Andrew.[SIGPIC][/SIGPIC]
amableson is offline   Reply With Quote
Old 19th April 2010, 11:36   #4
simdel1
Posted a thing or two
 
simdel1's Avatar
 
Rover 75 Connoisseur SE CDTi, Porsche 944 Lux, MGF

Join Date: Nov 2009
Location: Stamford
Posts: 1,088
Thanks: 4
Thanked 6 Times in 6 Posts
Default

My car does this too, but i've only noticed it if I've been running under 1/4 of a tank. Since reading this forum I've not let it drop below 1/2 a tank, because I'm trying to look after the fuel pumps, so I don't notice it any more.
__________________
Simon

The Simdel1 Fleet:
http://img593.imageshack.us/img593/447/sigmgf.png
simdel1 is offline   Reply With Quote
Old 19th April 2010, 15:37   #5
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

Running the trip screen's Diagnostic Mode under Test 6 may shed some light onto what's happening with each sender unit.

TC
T-Cut is offline   Reply With Quote
Old 19th April 2010, 21:16   #6
rossocorsa
Posted a thing or two
 
None

Join Date: Feb 2010
Location: GRIMSBY
Posts: 1,243
Thanks: 0
Thanked 1 Time in 1 Post
Default

Quote:
Originally Posted by T-Cut View Post
Running the trip screen's Diagnostic Mode under Test 6 may shed some light onto what's happening with each sender unit.

TC
spooky great minds think alike! just come inside from doing just that! both sender units show as giving good signal but one is showing very low even though the tank is getting on for half full!! I guess one only floats properly when there is some vibration on the move but sinks when parked?? not really worth messing with at the moment more pressing renovations to do as not had the car long
rossocorsa is offline   Reply With Quote
Old 19th April 2010, 21:48   #7
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

The float could be punctured, but I couldn't explain the variability in output. If any work has been done in the tank, the faulty float may not have been re-installed properly and could be rubbing on something. They are very sensitive to the innards of the tank.

As a matter of interest for keeping the diagnostic routine up to date, what did the screen display actually say?

TC
T-Cut is offline   Reply With Quote
Old 20th April 2010, 00:54   #8
Leander
Gets stuck in
 
Rover 75 Tourer CDT 02, Connoisseur SE in Royal Blue Pearlescent + XPower Upgrade & Synergy 2

Join Date: Sep 2009
Location: Lancaster
Posts: 591
Thanks: 1
Thanked 3 Times in 2 Posts
Default

If it's any consolation, my fuel gauge (2002 CDT 75 Tourer) behaves very like the one described.

Moreover, how much it shows seems to be linked in some arcane way to how I'm driving.

If I'm driving economically - as I usually I am - it rises a little sometimes on a trip - as if to reward me almost for my good behaviour.

But then will it fall suddenly and dramatically if I put my foot down - as if it is trying to tell me that if I drive like that for much longer I'll soon be out of fuel.

I thought this phenomenon might be the product of some bored Rover engineers' errant creativity, but how knows.

Cheers
Leander
Leander is offline   Reply With Quote
Old 20th April 2010, 06:23   #9
rossocorsa
Posted a thing or two
 
None

Join Date: Feb 2010
Location: GRIMSBY
Posts: 1,243
Thanks: 0
Thanked 1 Time in 1 Post
Default

Quote:
Originally Posted by T-Cut View Post
The float could be punctured, but I couldn't explain the variability in output. If any work has been done in the tank, the faulty float may not have been re-installed properly and could be rubbing on something. They are very sensitive to the innards of the tank.

As a matter of interest for keeping the diagnostic routine up to date, what did the screen display actually say?

TC
I'll try to investigate more thoroughly when I have time for instance take reading as soon as I have got home then a few hours later. I suspect a pin hole in the float as most likely
rossocorsa is offline   Reply With Quote
Old 20th April 2010, 14:49   #10
savvy
Avid contributor
 
MG ZT-T

Join Date: Feb 2010
Location: Fleet
Posts: 162
Thanks: 4
Thanked 5 Times in 5 Posts
Default

If you notice, the only people that report this "problem" drive CDT/CDTi's

This happens on my fathers 75 CDT and my ZT CDTi and a number of others.

I'm not sure if this is down to BMW algorithms with the fuel gauge/tank range, but it appears to be normal behavior.
savvy is offline   Reply With Quote
Reply

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 Off

Forum Jump


All times are GMT. The time now is 12:58.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd